2005 ALSO® Syllabus Update G: Malpresentations, Malpositions, and Multiple

Evidence Review completed: October 18, 2005 By Allan Wilke, MD and Harry (Chip) Taylor, MD, MPH Update published: December 6, 2005

SORT A Recommendation • Planned cesarean birth reduces , neonatal mortality, and serious neonatal morbidity compared to planned vaginal breech delivery.

SORT B Recommendation • Planned cesarean birth does not reduce the risk of death or neurodevelopmental delay in children at 2 year follow-up compared to planned vaginal breech delivery.

A Cochrane Review1 of 3 RCTs with a total of 2396 breech deliveries found that planned cesarean birth (PCB) led to a reduction in perinatal/neonatal morbidity and mortality when compared to planned vaginal birth (PVB). PCB was associated with a corresponding increase in short-term maternal morbidity. (See table below).

The Term Breech Trial2 was the largest of the 3 RCTs and drove the conclusions of the Review. It was the only RCT with long term follow-up; 920 infants and 917 mothers were evaluated 2 years after . The infant outcomes (death or neurodevelopmental delay) were similar in PCB and PVB groups.3 Maternal outcomes in the two groups (including perineal pain, back pain, sexual problems, painful intercourse, incontinence, and others) were also similar.3

Outcomes # Events/Patients Relative Risk NNT/ (%) (95% Confidence NNH** PCB PVB Interval) Perinatal/neonatal death or severe 17/1039 52/1039 0.33 (0.19-0.56) 30 neonatal morbidity* (1.64%) (5.00%) Perinatal/neonatal death 3/1166 14/1222 0.29 (0.10-0.86) 112 (0.26%) (1.15%) Maternal morbidity (short-term) 107/1169 106/1227 1.29 (1.03-1.61) 196 (9.15%) (8.64%) Death or neurodevelopmental delay 14/457 13/463 1.09 (0.52-2.30) *** at age 2 years* (3.06%) (2.81%)

* Combined outcome ** NNT is the number needed to treat; NNH is the number needed to harm. *** Since the 95% Confidence Interval includes 1.00, the result is not statistically significant and the NNH is not calculated. Fatal anomalies were excluded from the perinatal/neonatal death rates.

The American College of and Gynecology (ACOG) issued an Opinion4 noting that reduction in risk from cesarean versus planned vaginal breech delivery is greatest in industrialized nations with low perinatal mortality rates. ACOG concludes that planned vaginal delivery of a singleton term breech may no longer be appropriate.

2005 ALSO® Syllabus Update G: Malpresentations, Malpositions, and Multiple Gestations

ALSO® acknowledges the important implications of this new evidence and the recommendations of the ACOG Committee. ALSO® does not advocate routine vaginal delivery for breech presentation. However, the decision how best to deliver a breech presentation is complicated and may be based on consideration of many factors, including the patient’s informed consent.

Because unanticipated breech vaginal deliveries do occur, obstetrical caregivers need to have the knowledge and skills to safely handle this situation. It is for this reason that ALSO® teaches a standard method to prepare ALSO® providers to manage a vaginal breech delivery.

1 Hofmeyr GJ, Hannah ME. Planned for term breech delivery. The Cochrane Database of Systematic Reviews 2005, Issue 4. [Evidence level 1, systematic review of RCTs] 2 Hannah ME, Hannah WJ, Hewson SA, et al. Planned caesarean section versus planned vaginal birth for breech presentation at term: a randomised multicentre trial. Term Breech Trial Collaborative Group. Lancet. 2000;356(9239):1375-1383. [Evidence level 1, RCT] 3 Hannah ME, Whyte H, Hannah WJ, et al. Maternal outcomes at two years after planned cesarean section versus planned vaginal birth for breech presentation at term: the International Randomized Term Breech Trial. Am J Obstet Gynecol. 2004;191:917-927. [Evidence level 2, prospective cohort study] 4 ACOG committee opinion: number 265, December 2001. Mode of term single breech delivery. Obstet Gynecol. 2001;98:1189-1190. [Evidence level 3, consensus guideline] G: Malpresentations, Malpositions, and Multiple

(slide 1) Steven H. Eisinger, M.D.

Objectives (slide 2) At the end of this lecture / discussion and workstation, participants will be able to: 1. Define six types of malpresentations and methods for diagnosis. 2. List complications associated with each malpresentation. 3. Discuss the criteria for allowing vaginal delivery, and the management of vaginal delivery, when appropriate. 4. Discuss multiple gestation, with special attention to labor and delivery. 5. Perform safe, effective delivery of various malpositions and malpresentations using the maternal-fetal mannequin.

Definitions (slide 3) Definitions are important to a discussion of malpresentations. Lie refers to the relationship of the long axis of the fetus to that of the mother, specified as longitudinal, transverse, or oblique (also referred to as unstable). Presentation refers to the portion of the fetus that is foremost or “presenting” in the birth canal. The fetus may present by its vertex, breech, face, brow, or shoulder. refers to a reference point on the presenting part, and how it relates to the maternal pelvis. For example, the reference point on the vertex is the occiput. When the fetal occiput is directed toward the mother’s symphysis, or anteriorly, the fetus is in occiput anterior (OA) position. When the occiput is directed toward the maternal spine, the fetus is occiput posterior (OP). Intermediate positions around the compass are left and right occiput anterior (LOA and ROA), left and right occiput transverse (LOT and ROT), and left and right occiput posterior (LOP and ROP).

Methods of Diagnosis (slide 4) There are three principal methods of determining fetal lie, presentation, and position. The first is Leopold’s maneuvers or abdominal palpation. The second method is vaginal exam. The third method is imaging. Ultrasound is the preferred imaging method. Labor floor ultrasound examination is widely utilized in hospitals

G: Malpresentations, Malpositions, and Multiple Gestation 1 of all sizes, and every birth provider should have acquaintance with ultrasound skills in this setting to determine fetal lie, presentation, and position. Occasionally x-ray is necessary, particularly when fine detail is needed, such as the position of the limbs in a breech.

Incidence of Malpresentations at Term1,2

Malpresentation Incidence Percent Occiput posterior 1 in 10 to 20 5 to 10 Breech 1 in 25 to 33 3 to 4 Transverse lie or shoulder presentation 1 in 322 to 420 0.3 to 0.23 Face 1 in 500 to 1200 0.2 to 0.08 Compound presentation 1 in 700 to 2235 0.14 to 0.047 Brow 1 in 4470 0.02

The Fetal Head and the Maternal Pelvis (slide 5) Most fetal malpresentations (posterior, breech, face, brow) are clinically significant because the fetal head is not round, but rather ovoid or egg-shaped. The smallest of the fetal diameters is the suboccipitobregmatic; the largest is the occipitomental. The difference between them is three centimeters, or about 24 percent. When the head is in full flexion, the suboccipitobregmatic or smallest diameter presents to the pelvis. When the head is in full extension (or deflexion) the occipitomental or largest diameter presents. Delivery is much more likely to occur, and will be easier, if a smaller diameter presents. Therefore, the attitude of the fetal head (flexion versus extension) as it presents to the pelvis is of paramount importance. A degree of fetal extension of the head occurs with OP presentations, face and brow presentations, and some breeches. (slide 6) Asynclitism also plays a major role in the mechanics of labor. Asynclitism is lateral flexion of the head, such that the sagittal suture is not in the middle of the birth canal. Some degree of asynclitism is normal, and the fetal head may even shift back and forth from anterior to posterior asynclitism as the head accommodates more deeply into the pelvis. Extreme degrees of asynclitism may prevent labor from progressing. Asynclitism becomes a major factor in adequate forceps application.

G: Malpresentations, Malpositions, and Multiple Gestation 2 The maternal pelvis also plays an important role in the cause of various (slide 7) malpresentations and prognosis for delivery. There are four pure types of pelves. Most women have a gynecoid or intermediate type: • Gynecoid (round) • Anthropoid (oval, with the long axis in the AP plane) • Platypelloid (oval, with the long axis in the transverse plane) • Android (triangular or heart-shaped, with the apex of the triangle anteriorly) While a full discussion of pelvic types and is of limited clinical usefulness, it can be generalized that a narrow pelvis such as the anthropoid can cause persistent occiput posterior; the platypelloid pelvis can cause a transverse arrest; the android pelvis is prejudicial to delivery with all malpresentations; and an inadequate or small pelvis can be associated with most of the malpresentations, mainly based on the inability of the head to descend, engage, or rotate.

Occiput Posterior Position In the Occiput Posterior (OP) position, the fetus lies with its occiput towards the mother’s spine and its face towards the mother’s symphysis and abdomen. In other words, the fetus is face up when the mother is supine or in lithotomy position. Usually the fetus in occiput posterior position will rotate spontaneously to occiput anterior (OA) and deliver spontaneously. Spontaneous rotation fails to occur in five to ten percent of cases, and the fetus remains in persistent occiput posterior position. The exact cause of persistent OP is unknown, but transverse narrowing of the pelvis plays a role. All occiput posterior fetuses are somewhat deflexed because the vertex drops back to fill the hollow of the sacrum. The combination of deflexion and posterior presentation causes less favorable diameters of the fetal head to present to the pelvis than when the fetus is in the occiput anterior position. (slide 8) The diagnosis of OP is based on observation of the patient and examination. Ultrasound imaging can be helpful but is sometimes confusing. Easy palpation of the anterior fontanel on vaginal exam is a diagnostic aid in determining OP position. This is true because the anterior fontanel is most easily felt when the head is somewhat deflexed. If the anterior fontanel is palpated, then one must identify the sagittal suture. This can be accomplished by following each suture with the examining finger until the posterior fontanel is encountered. Occasionally an ear can be palpated, revealing the fetal position. The exam can be confusing due to molding, overriding of sutures, edema, and asynclitism. Dilation is often asymmetric and a persistent anterior lip is common. Back pain, or “back labor,” is a clinical hallmark of OP position.

G: Malpresentations, Malpositions, and Multiple Gestation 3 The diagnosis of OP can be very difficult. Most obstetric care providers have had the experience of making the diagnosis at the last minute when the fetal head seems to fill the posterior pelvis as it delivers, or even later as the fetal face becomes visible under the symphysis. In the “old days” even skilled operators occasionally rotated babies “the wrong way,” from OA to OP, to the delight of their residents! (slide 9) The conduct of labor and delivery with a persistent OP is not markedly different from that of the fetus in the occiput anterior position.1 (Category C) The progress of labor can be followed by and the descent of the vertex through the birth canal. Labor with OP position is prolonged on the average for one hour in parous women, and two hours in nulliparous women. Perinatal mortality does not differ significantly from OA, and there is no significant difference in Apgar scores. However, perineal lacerations and extensions of episiotomies may be increased because the vertex sweeps through the posterior pelvis, larger diameters are presented to the pelvic outlet, and the occiput places maximal pressure on the perineum as it delivers. There are five possibilities for vaginal delivery when persistent occiput posterior occurs: 1. Spontaneous Delivery – Spontaneous delivery occurs 45 percent of the time in one study utilizing expectant management.3 Because the fetal head cannot stem upward until the face has cleared the symphysis, the fetal vertex must pass through the posterior pelvis, where it places strain on the perineum. These babies look like they “want” to deliver through the rectum. However, frequently the delivery is easy. (slide 10) 2. Manual Rotation – and labor and delivery nurses have long held that fetuses in OP position can be turned by placing the laboring woman in various positions such as on her side, squatting or ambulating, on hands and knees, or with her back arched (to make the fetus uncomfortable, so it turns itself!). Failing these maneuvers, manual rotation becomes an attractive alternative during a long second stage of labor because it can be attempted during any vaginal exam. If successful, delivery may be greatly expedited; if unsuccessful, no harm has been done. The key to manual rotation is to enhance the natural and normal forces of rotation. Rotation normally occurs when the flexed fetal head strikes the muscles of the pelvic floor, known as the levator sling. The operator must first therefore flex the fetal head. This is accomplished by placing a hand in the posterior pelvis behind the occiput. The operator’s hand essentially replicates and enhances the levator sling effect, acting like a wedge to flex the head. Then rotatory force is applied to the head, using for purchase any fontanel or suture that may be felt with the examining fingers. Some operators grasp the head with the thumb as well. The rotation should be attempted at the same time as a contraction, and with the mother pushing as well, to force the head down on the levator sling (and the hand), which is

G: Malpresentations, Malpositions, and Multiple Gestation 4 the natural mechanism for flexion and rotation. An experienced assistant may massage the fetal shoulder in the direction of the rotation with suprapubic or abdominal pressure. Manual rotation may be attempted with the patient in lithotomy position, or lateral Sims’ position, or on hands and knees. In the hands and knees position the abdominal assist is impractical. A commonly encountered question relates to which hand should be used to rotate the fetus. If the fetus were straight OP, the operator would naturally use his/her dominant hand. But, if the fetus were already rotated somewhat, either in the ROP or LOP position, then rotation should go “the shortest distance”. Therefore, an ROP should be rotated clockwise, and a LOP should be rotated counterclockwise. The hand should be used which pronates during the rotation (like closing a book): left hand for ROP and right hand for LOP.4 (Category C) Manual rotation is part of the “gentle art” of obstetrics. It is a neglected skill, but one which requires no technology or instrumentation. Risk is minimal. With practice, confidence and skill improve. Successful manual rotation may shorten the second stage of labor and avoid instrumentation, or even a cesarean delivery. (slide 11) 3. Vacuum Delivery – Vacuum delivery is an attractive option in persistent OP presentation. The vacuum cup may safely be applied even when the operator is not completely confident of the exact position of the head, due to molding, edema, and overriding of sutures. The vacuum may successfully draw the head out in the OP position. Alternatively, in flexing the head and drawing it down against the levator sling, the vacuum may promote rotation. Delivery will then occur in the OA position. The vacuum allows the fetal head to find its own best plane for delivery. Many operators have been startled to see the head rotate 180 degrees as they tract, sometimes in the very moment before delivery. The vacuum cup should be placed as far posteriorly on the head as possible to promote flexion. (See Chapter H. Assisted Vaginal Delivery) No direct rotary force should be applied to the cup, as this may cause “cookie cutter” type injury to the scalp, and also may cause the cup to disengage. The mechanism of delivery for an OP is the same with a vacuum as with forceps or a spontaneous delivery: the fetal vertex takes a more posterior course through the pelvis. As with any vacuum delivery, the shaft of the extractor must be kept at right angles to the plane of the cup, or detachment will occur.

G: Malpresentations, Malpositions, and Multiple Gestation 5 (slide 12) 4. Forceps Delivery – The usual indications for forceps delivery apply. Forceps fit the occiput posterior vertex equally as well as the occiput anterior vertex. The mere presence of an OP presentation is not in itself a sufficient indication for forceps use. The mechanism of delivery is the same as for a spontaneous OP delivery. The head is actually born by flexion, not extension. The fetal face must pass beneath the symphysis before the head can flex upward, so traction on the forceps must be in a more posterior direction for longer than with OA deliveries. Pressure on the perineum can be intense with resulting third and fourth degree lacerations. Occasionally, with an occiput posterior and a prolonged second stage, severe molding and edema will occur. Then the fetal vertex will present in the midpelvis or even on the perineum, but careful exam will reveal that the fetal head is very elongated and the biparietal diameter is not even engaged. Under such circumstances attempts at operative delivery are not likely to be successful, and may even be hazardous. Cesarean delivery is indicated, at which time the lack of engagement may be confirmed by the ease with which the fetus is lifted out of the pelvis. 5. Forceps Rotation – Only skilled operators trained in the Scanzoni or Kielland techniques should consider forceps rotation. In most American hospitals, these techniques are seldom practiced now. Cesarean delivery should always be the backup method of delivery for any OP presentation that cannot be safely delivered vaginally.

Breech Presentation Breech presentation is defined as the fetal breech or buttocks presenting in the (slide 13) birth canal, with the head aftercoming in the uterine fundus. Breech presentations may be classified as follows: • Frank breech: hips flexed and legs extended over the anterior surface of the body, occurring in 45 to 50 percent of breeches. • Complete breech: (also called Full): hips and legs flexed (tailor sitting or squatting), occurring in 10 to 15 percent of breeches. • Footling breech: one or both hips and knees extended with one or both feet presenting, occurring in 35 to 45 percent of breeches. (slide 14) Breech presentation has many predisposing factors. Prematurity is commonly associated with breech, and as the fetus approaches term the incidence of breech drops to three to four percent.

G: Malpresentations, Malpositions, and Multiple Gestation 6 Fetal Presentation at Various Gestational Ages Modified from Scheer and Nubar5

Gestation (weeks) Percent breech 21 to 24 33 percent 25 to 28 28 percent 29 to 32 14 percent 33 to 36 9 percent 37 to 40 7 percent

Other predisposing factors include high parity and relaxation of the uterine and abdominal wall; uterine anomalies; pelvic tumors; ; oligohydramnios; various fetal anomalies including hydrocephalus, anencephaly, and Down Syndrome; macrosomia; multiple ; previa; absolute cephalopelvic disproportion; and previous breech. Because of these associated factors, a formal ultrasound with a fetal anatomical survey is indicated when the diagnosis of breech is made in the mid-third trimester or later. Often, no cause is found.

Diagnosis The diagnosis of breech can often be made by abdominal palpation and vaginal exam. On Leopold’s maneuvers, the firm, ballotable, rounded head is felt in the fundus. On vaginal exam, either small parts or the breech itself may be detected. If small parts are palpated, it is essential to distinguish between a hand and a foot. The breech itself is smooth and rounded, and may feel remarkably like a vertex. Most providers have had the experience of “missing a breech” on vaginal exam. The key is to seek fontanels and sutures with the examining finger, which always signify a vertex. In breech presentation, the anus and ischial tuberosities form a straight line, whereas the mouth and malar prominences form a triangle. Additionally, the skin of the fetal buttock is smooth. An alert examiner can distinguish it from the hairy feel of the scalp. This subtle sign may raise an examiner’s index of suspicion to perform a more definitive exam. If the examiner’s finger encounters an orifice, then the finger can be gently inserted into the orifice. If it is the mouth, (signifying a face presentation) the fetus will suck on the finger. If it is the anus (signifying a breech), the finger will be coated with meconium when withdrawn.

G: Malpresentations, Malpositions, and Multiple Gestation 7 Prenatal Management of Breech (slide 15) There are four elements to the prenatal management of breech. First, a cause must be sought for the breech presentation. Most of the causes of breech presentation that can be identified are detectable by ultrasound. Secondly, the patient may attempt certain exercises to turn the breech. Thirdly, external cephalic version may be contemplated and attempted. Fourthly, failing successful version, a decision must be reached regarding the most favorable mode of delivery.

Postural Management of Breech Presentation (slide 16) Various exercises and positions have been tried in an attempt to turn a breech. No difference in outcome has been noted in a review of trials in which women were randomized to either a postural management group or a control group.6, 7 (Category C) The exercises themselves are simple. One version of the exercises is for the woman to assume a knee-chest position for 15 minutes three times a day, for five days after the diagnosis of the breech. Another version is for the woman to assume a deep Trendelenburg position by elevating her hips nine to twelve inches while lying supine, for ten minutes once or twice a day. Pelvic rocking while in either of these positions is often recommended. While efficacy cannot be proven, these exercises do no harm, and they do provide a focus of activity for an anxious gravida (and maternity care provider!). There are no contraindications to doing these exercises.

External Cephalic Version (ECV) External cephalic version, or turning a breech fetus to vertex by manipulation through the mother’s abdominal wall and uterus, has become an accepted component of the prenatal management of breech presentation. Williams Obstetrics (20th Edition), the Cochrane Data Base, and ACOG Practice Bulletin (Feb. 2000 #13) all support ECV for breech presentations. 8,9,10 This procedure is low tech and low cost, can lower cesarean delivery rates, saving these women from potential operative morbidity. The risk of an adverse event occurring as a result of ECV is small, and the cesarean delivery rate is significantly lower among women who have undergone successful version. Women near term with breech presentations should be offered a version attempt. 9,10 (Category A) The success rate of ECV, averaged from many studies, is 58 percent. In a comprehensive program of ECV, cesarean delivery for breech can be reduced by (slide 17) half. Factors associated with success of ECV are: parity, frank breech presentation, normal or increased , and a relaxed uterus. Negatively associated with success are: nulliparity, obesity, oligohydramnios, anterior placenta, and low station of the breech. The operator’s skill and the patient’s tolerance of the procedure also play a large role in success. is

G: Malpresentations, Malpositions, and Multiple Gestation 8 also a factor in the success rate. Prior to 37 weeks, the initial success is good, but reversion is common. Furthermore, if expedited delivery becomes necessary, the fetus is premature. ECV after 37 weeks has a significantly lower success rate. This gestational age appears to be optimal for ECV, as the success rate is still good, the reversion rate back to breech is low, and, should immediate delivery be necessary, the fetus is sufficiently mature.9,10 (Category A) ECV in early labor is difficult, although some success has been reported. (slide 18) Several contraindications to ECV exist: multiple pregnancy (although ECV is a good potential management strategy for a breech second twin), non-reassuring fetal heart rate tracing, utero-, uterine anomalies, placenta previa or unexplained bleeding, and maternal medical conditions such as cardiac disease or pregnancy-induced hypertension. One small, randomized study examined ECV in patients with previous cesarean delivery; success was good and uterine rupture did not occur.11 Various strategies have been employed to increase the success of ECV. Routine tocolysis appears to reduce the failure rate of external cephalic version at term. Although promising, there is not enough evidence to evaluate the use of fetal acoustic stimulation in midline fetal spine positions.12 There is not enough evidence to evaluate the use of epidural analgesia or transabdominal amnioinfusion for external cephalic version at term.12 (slide 19) Complications of ECV are infrequent. Fetal bradycardia and decelerations are common, noted in 40 percent of cases, but usually resolve spontaneously or with cessation of the procedure. Sporadic reports have been noted of abruption, fetal hemorrhage, maternal hemorrhage, knotted or entangled cord, fetal mortality, and maternal mortality due to amniotic fluid embolism. A 1993 report noted no fetal deaths since 1980.13 When performing ECV, facilities and personnel must be available for performing an immediate cesarean delivery.13 (Category C)

G: Malpresentations, Malpositions, and Multiple Gestation 9 Procedure for External Cephalic Version (This is a sample protocol similar to many published protocols. Other variations exist.) Preparation: • Patient may be accompanied by support person • Patient NPO (nothing by mouth) • Patient gowned, bladder empty • Confirm breech by ultrasound and rule out fetal anomalies • Perform NST () or BPP (biophysical profile) • Obtain consent • Cesarean delivery personnel and facilities available • Intravenous access • Tocolysis (recommended for primagravidas; optional for multiparas): 0.25 mg of terbutaline (subcutaneous) 15 minutes before starting the procedure, or any approved tocolytic regimen • Position: supine, slight left lateral tilt, Trendelenburg, knees slightly bent • Abdomen coated with ultrasound gel

Procedure (for two operators) (slide 20) • Operator #1 elevates breech from pelvis by driving a hand suprapubically beneath the breech. • Operator #1 pushes the breech into the iliac fossa. (slide 21) • Operator #2 flexes the head (for a forward roll), and rotates the fetus into an oblique lie. • Two thirds of the force or pressure should be applied to the breech, and one third of the force should be applied to the head. Avoid excessive force. Use a massaging motion when possible rather than direct steady pressure. • Both operators should rotate the fetus slowly around. Just enough force or pressure should be used that moves the fetus. Progress will occur in stages, or “cogwheel” fashion. The fetus will rotate slightly, then resist, then rotate more. Allow the mother and fetus brief rest periods when resistance is felt, while attempting to maintain the progress already achieved. (slide 22) • Monitoring may be by ultrasound or doppler, and should be performed every 30 seconds, during rest periods. (slide 23) • When the fetus is just past the transverse, it may rotate the rest of the way without effort, as it accommodates to the shape of the uterus • The vertex may be guided gently over and into the pelvic inlet with suprapubic manipulation and fundal pressure. (slide 24) • Ultrasound to confirm success. • After successful version, monitor for 20 to 30 minutes or until a reactive pattern occurs. • If the ECV is very easy, or if it is a second ECV after a fetus has reverted to breech, then a binder may be placed on the abdomen to hold the fetus in place, and induction initiated. • In Rh negative patients, administer D-immune globulin (Rhogam ®); may obtain Kleihauer-Betke test. • If the forward roll fails, then try a backward flip, especially if the vertex and breech lie on the same side of the maternal midline. • This procedure can be strenuous for the operators. A third operator can relieve the other two at intervals. • If no success by 15 to 20 minutes, then discontinue the procedure. • If the patient feels sharp pain, stop the procedure. • If bradycardia occurs, stop the procedure. If it persists, then revert the fetus to its original breech position. If the bradycardia still persists, then prepare for cesarean delivery.

G: Malpresentations, Malpositions, and Multiple Gestation 10 Choosing Route of Delivery for Breech The optimal route of delivery for breech infants has been the subject of much controversy. Currently, in the United States, most breeches (well over 90 percent in some institutions and nearly all primagravidas) are delivered by cesarean delivery. However, rigorous support for this practice has been lacking in the literature. Numerous studies have shown the safety of vaginal delivery for selected breeches. Additionally, cesarean delivery does not prevent all infant morbidity, which, in some cases, arises from the same problems that caused the breech presentation in the first place.14 A Cochrane review suggests that adequate evidence does not exist to evaluate the use of a policy of planned cesarean section for breech presentation.15 However, a multi-center, international, randomized controlled trial compared elective cesarean delivery to vaginal delivery for selected breech presentations: greater than 37 weeks, frank or complete breech, and less than 4000 grams estimated fetal weight.17,18 This trial was terminated early, in April 2000, after preliminary data analysis showed significant reduction in perinatal mortality and morbidity, and no increase in serious maternal complications, in the elective cesarean group.17 Two considerations, not strictly medical, enter into the decision regarding cesarean versus vaginal delivery. First, the skills to perform a safe vaginal breech delivery are not being taught in many residencies, and practitioners who retain these skills are aging. Second, the medical-legal ramifications of vaginal delivery are prohibitive in the minds of many. (slide 25) Certain contraindications exist for elective vaginal delivery of breech infants: • Unfavorable pelvis: if the pelvis is known to be small, or if it is android or platypelloid, vaginal delivery should not be attempted. X-ray or CT pelvimetry have not been shown to improve outcomes for breech births. • Macrosomia (defined variously, from 3800 grams upward). • Severe prematurity (defined variously). • Intrauterine growth restriction or evidence of placental insufficiency. • Footling breech. • Hyperextension of the fetal head: delivery can be difficult, and labor can result in neurological injuries with a hyperextended head. An X-ray of the abdomen may be necessary to determine the attitude of the fetal head. • Fetal anomalies such as hydrocephalus. • Nuchal arm: again an x-ray is required to diagnose this condition. • Absence of labor, as in premature , or non- progressive labor: induction and augmentation of labor are controversial in the literature, but often avoided in favor of cesarean delivery. • Lack of a physician with the experience and skill necessary for vaginal delivery.

G: Malpresentations, Malpositions, and Multiple Gestation 11 Various scoring systems have been developed to predict outcome of vaginal breech delivery. The best known of these systems is the Zatuchni-Andros Prognostic Scoring Index. It awards points for parity, gestational age less than 37 weeks, estimated fetal weight less than seven pounds, previous breech delivery, dilation at presentation, and station at presentation.16 This system has several faults, among them rewarding prematurity, and also rewarding the gravida who stays home to labor, thus presenting at a greater dilation and lower station. However, no better-validated system of predicting breech outcome has been developed. In summary, the decision as to the best mode of delivery of a breech is complicated. Many factors must be taken into account, including the best conclusions from the medical literature, community and national standards, the specifics of each individual case, the patient’s wishes, and the skill of the operator.

Labor and Delivery Presented here is a standard method of delivering a breech per vagina. Variations of this method exist. ALSO® offers this technique as not necessarily the only one, nor even the best, but one which is widely accepted by American practitioners and which can be learned and practiced on the mannequin. ALSO® acknowledges that vaginal breech deliveries do occur, sometimes emergently under circumstances in which cesarean delivery or consultation are not possible. Therefore, every obstetric provider should have a working knowledge of how to deliver a breech.

(slide 26) There are fundamental differences in delivery between cephalic and breech presentations. With cephalic or vertex presentation, the largest part of the fetus, the head, delivers first. Molding of the cranium can occur over several hours. With a breech delivery, first the breech, then the shoulders, then the head delivers, each larger and less compressible than the previous part. Molding of the head has no opportunity to occur because the fetal head is in the pelvis only for a few minutes, and because it enters the pelvis with the base of the skull leading, which, unlike the vertex, cannot mold. The great challenge of the vaginal breech delivery is that the last part of the fetus to deliver is also the largest part, and it might not fit through the pelvis.

G: Malpresentations, Malpositions, and Multiple Gestation 12 Labor with a breech is not very different from labor with a vertex, and may be allowed to continue spontaneously as long as progressive dilation and descent occur, and there is no fetal or maternal compromise. A frank breech will distend the perineum and dilate the introitus in a manner similar to a vertex. Episiotomy is often recommended. While episiotomy will not create more room in the bony pelvis, it will enable the operator to perform various manipulations more easily, including emergency procedures such as Piper forceps application. Episiotomy is very difficult to perform once the whole body is out. (slide 27) The frank breech usually delivers with the axis of the hips in the AP plane, and the fetal sacrum will either be to the left or the right. Usually, the anterior hip descends to the introitus and passes below the symphysis in a manner analogous to the anterior shoulder. Then with lateral flexion of the fetal body, the posterior hip delivers over the perineum. The operator may support the perineum with a Ritgen- type maneuver, or the breech may be allowed to deliver spontaneously. External rotation follows delivery of the breech, allowing the infant’s back to turn anteriorly. Delivery should proceed spontaneously until the fetal umbilicus appears at the introitus. The mother should be making strong, but controlled, pushing efforts at this point in the delivery. Traction by the operator prior to delivery of the umbilicus may promote extension of the fetal head or nuchal placement of the arms. Do not pull on the fetus until the umbilicus is delivered, and, even then, traction is not necessary if the delivery continues to progress. When the umbilicus delivers, a loop of several inches of cord should be gently pulled down. This prevents tension on the cord as the body delivers, and also allows easy monitoring of the fetal pulse by palpation. (slide 28) The legs of a frank breech may be delivered by inserting a finger behind the knee to flex the knee and abduct the thigh. Active efforts to deliver the legs are not mandatory, as the legs will deliver spontaneously and the feet will “spring” free eventually. Delivery of the legs in this manner can be accomplished, before the breech has delivered, by a skilled practitioner who is attempting a total breech extraction. (slide 29) After the umbilicus is born, gentle downward traction may be used to deliver the infant’s torso. The fetus may be grasped by the operator’s fingers on the fetal pelvis, with thumbs on the sacroiliac regions. This avoids placing the hands too high on the fetus and injuring abdominal organs such as the spleen or liver. Traction should be in a 45-degree downward axis, toward the floor. It is helpful for the operator to assume a position below the fetus, as for example on one knee in front of a delivery room table. The fetal trunk may deliver quickly and without operator effort, or considerable effort may be required to deliver the trunk. Rotation of the fetal back from one anterior oblique to the other anterior oblique may be helpful in extracting the

G: Malpresentations, Malpositions, and Multiple Gestation 13 trunk, and it also encourages the fetal arms to gather in a flexed position across the chest. This rotatory maneuver carries an eponym in Great Britain, where it is called the Lovsett maneuver. Of critical importance is keeping the back up during the delivery, which allows the fetal head to enter the pelvis occiput anterior. If the fetus rotates abdomen up, the fetal head will present very unfavorable diameters to the maternal pelvis, severely jeopardizing safe delivery. (slide 30) Delivery of the arms is accomplished by rotating the fetal body into the oblique. The tip of the fetal scapula will come into view, usually quite easy to identify because it is “winged.” The anterior arm may then be swept down across the fetal chest and out of the introitus. If possible, the humerus should be splinted with two fingers rather than simply hooking the antecubital fossa with a finger. Rotation of the fetus into the opposite oblique allows delivery of the opposite arm in a similar fashion. Delivery of the head follows, and is potentially the most difficult and hazardous part of the breech delivery. The head must be born by flexion through the pelvis. When the breech head is flexed and occiput anterior, and then passes through the birth canal by further flexion, the same favorable diameters are presented to the pelvis as in the case of a vertex occiput anterior delivery. (slide 31) A modification of the Mauriceau Smellie Veit (MSV) maneuver is recommended to deliver the head by flexion. Everything about the MSV maneuver is designed to promote flexion. One of the operator’s hands should be placed above the fetus with one finger inserted into the vagina and placed on the occiput, and one finger on each of the fetal shoulders. The other hand is placed beneath the fetus. The classical MSV maneuver describes placing a finger in the mouth, but this is not recommended because traction on the jaw can cause dislocation. As an alternative, two fingers may be placed on the maxillae. A very competent assistant should follow the head abdominally, and be prepared to apply suprapubic pressure to flex the head through the pelvis. The fetus may be wrapped in a sling that is also held by an assistant, or may be draped on the operator’s lower arm. Delivery of the head then commences. The head is flexed through the pelvis by four separate mechanisms: the occipital finger applies flexing pressure on the occiput; the assistant applies suprapubic pressure on the occiput as well; the fingers on the maxillae apply pressure on the lower face, which tends to promote flexion. The fetal body is raised upward by the sling in a large arc. While strong, controlled expulsive efforts by the mother are most helpful, some traction is also required for the delivery. This is accomplished by downward pressure of the fingers on the shoulders. The assistant holding the fetus by a sling may also hold the feet, and pull gently as the body describes its arc. The fetal body should stay in a neutral position with regard to the head, avoiding hyperextension. Ultimately, the body becomes upside down and vertical, and at this point an assistant must hold the feet to prevent the fetus from falling on the floor.

G: Malpresentations, Malpositions, and Multiple Gestation 14 As the mouth and nose appear over the perineum they may be suctioned. The cranial vault then delivers by further flexion. The operator may use a Ritgen technique on the perineum. As the head finally emerges, the infant’s body actually flips over past vertical onto the mother’s abdomen. Extraction of a breech at cesarean delivery requires maneuvers similar to those used in vaginal birth. Thus cesarean delivery of a breech gives an opportunity for the surgeons to practice. The goal of cesarean delivery with a breech is to afford a gentle delivery. If the uterine or abdominal incisions prove to be too small for easy delivery, they can be enlarged. This is not an option during vaginal birth.

Piper Forceps Piper forceps are specifically designed to deliver the aftercoming head of a breech. They are very long, and have an axis traction curve built in. It is impossible to determine if a Piper application is “good” or “bad” on the fetal skull. Therefore, they are always applied the same way: straight to the maternal pelvis as if the position were OA. The blades are springy and grasp the fetal head in a non-specific basket catch that has proved safe and effective. Forceps are indicated when the MSV maneuver fails. Although strict guidelines are lacking, one should consider Piper forceps if two or three minutes have passed without progress while attempting the MSV maneuver. Pipers may also be applied prophylactically if a fetus is believed to be fragile, such as a premature fetus. It is prudent to have the Pipers readily available for any vaginal breech delivery, but in an emergency, any forceps will do. To apply Pipers, the fetus (including the arms) is wrapped in a sling and gently held up and to the operator’s left. The left blade is always applied first. It is held in the operator’s left hand and is applied to the left side of the mother’s pelvis (but to the right side of the fetus). Unlike other forceps applications, the operator holds the handle in a horizontal position and below the fetus. The right hand is placed in the vagina alongside the fetal head to protect the vaginal sidewalls. Then the forceps blade is insinuated between the right hand and the fetal head, following the cephalic curve of the blade around the head. Once inserted, the handle may be allowed to dangle or may be supported by an assistant. The right blade is then inserted in a similar fashion, by grasping the handle with the right hand and sliding the blade into the vagina alongside the head, while protecting the sidewall with the left hand. The forceps should then be locked. When the right blade is applied over the left blade the lock will articulate normally. The handles are usually separated slightly away from the lock, and should not be squeezed together. Since the operator cannot determine how the blade is applied to the fetal skull and face, no effort is made to do so. With the application completed, delivery of the head may commence. The operator applies a small amount of traction to the forceps. Since the shanks of

G: Malpresentations, Malpositions, and Multiple Gestation 15 the forceps have a large axis traction curve built in, no special maneuvers such as the Pajot maneuver are required to ensure that traction is in the correct vector. The primary motion of the forceps is to raise the handles in a large arc, starting about horizontal and ending at or past vertical. This arc will flex the head through the pelvis with exactly the same geometry as the MSV maneuver, but with greatly increased leverage due to the length of the forceps. None of the flexing maneuvers of the MSV maneuver are required when the Pipers are used. The fetus may be held in the sling or laid on the shanks of the forceps during the delivery. The principal difficulty in applying Pipers is a result of the condition that indicates their use: that is, failure of the MSV maneuver implies a tight fit of head to pelvis. There may be insufficient room to place a hand alongside the head. In this situation the blade must be applied “blind” with risk of injury to mother and fetus. Once the Pipers are on, delivery can be accomplished in almost every case.

Complications of Breech Delivery A nuchal arm may occur, that is, one or both arms may be extended upward behind the neck, which may impede delivery of the head. In this event there are three delivery options. If the fetus is small or the pelvis large, the head and extended arm may be delivered together. Alternatively, the operator may attempt to flex the arm and sweep it down over the face and chest. As a maneuver of last resort the operator may rotate the fetus 360 degrees in the direction that will sweep the arm out of its nuchal position (clockwise for a left nuchal arm, counterclockwise for a right nuchal arm). Entrapment of the aftercoming head by the cervix is another serious complication of breech delivery. This situation occurs primarily in premature and footling breeches in which the body has slipped through an incompletely dilated cervix. The head, being the largest part, becomes entrapped by the cervix. The problem is most severe in a nulliparous woman, whose cervix has never been fully dilated. (slide 32) Resolution without excessive traction may require cutting the cervix, a procedure known as Dührssen’s incisions. Ring forceps are placed in pairs, parallel to each other at 2:00, 10:00 and if possible 6:00, extending three to four centimeters into the cervix. A radial incision is made between the ring forceps of each pair. Anesthesia and exposure are major technical problems, and hemorrhage is a major potential complication. This procedure is recommended only in the most extreme life-threatening circumstances. Hydrocephalus may present as a breech delivery with an entrapped head. The appearance of a meningomyelocele or spina bifida may herald the hydrocephalus, occurring in about a third of such cases. Although prenatal diagnosis will call for highly individualized management and probable cesarean delivery, the unexpected diagnosis at the time of a breech delivery presents a significant

G: Malpresentations, Malpositions, and Multiple Gestation 16 dilemma. Decompression of the fetal ventricles or cephalocentesis may be prejudicial to the fetus, but the only way for the delivery to be completed. This procedure may be accomplished with a long needle either transvaginally or transabdominally.

Transverse Lie or Shoulder Presentation In transverse lie the long axis of the fetus is approximately perpendicular or at right angles to that of the mother. In the back down transverse lie or shoulder presentation, the shoulder is over the pelvic inlet, the head is lying in one of the iliac fossae, and the breech in the other. Transverse lie can also occur in the back up orientation, most commonly in the second twin. Occasionally an unstable or oblique lie will be noted, in which the fetus changes from a breech or vertex to a transverse lie or assumes an intermediate lie. Transverse lie occurs in about 0.3 percent of singleton births. The common causes of transverse lie are: unusual relaxation of the abdominal wall, preterm fetus, placenta previa, abnormal uterus (e.g. subseptate), contracted pelvis, tumor occluding the birth canal, and polyhydramnios.

Diagnosis The diagnosis of transverse lie is usually easily made by palpation. No presenting part will be felt suprapubically, and the head will be felt in the iliac fossa. On vaginal exam the pelvis will be empty. Imaging can confirm the diagnosis.

Mechanism of Labor and Management of Delivery Spontaneous birth of a full term fetus is impossible. Therefore, cesarean delivery is mandatory in most cases. If transverse lie is encountered before the onset of labor and rupture of membranes, an attempt at external cephalic version is reasonable assuming there are no contraindications to vaginal delivery, such as placenta previa. If a fetus presents with a back-up transverse lie and a fully dilated cervix, such as might be the case with a second twin, then either external cephalic version or internal podalic version may be contemplated. This is described in the section on multiple gestation. (slide 33) When labor ensues with a back down transverse lie, the shoulder is forced into the pelvis, and an arm may prolapse. With continued labor a retraction ring develops. Ultimately, in a neglected labor, the uterus ruptures and the mother and fetus risk death. This scenario is rarely seen in modern obstetrics but may be encountered in parts of the world where access to care is a problem.

G: Malpresentations, Malpositions, and Multiple Gestation 17 Cesarean delivery for a back down transverse lie may require a low vertical incision in order for the operator to successfully deliver one of the fetal poles through the uterine incision.

Face Presentation In a face presentation, the head is hyperextended so the occiput is in contact with the fetal back, and the face is the presenting part. The fetal skull diameter that presents to the pelvis is the submentobregmatic, which is favorable for delivery in most cases. The reference point on the fetus is the chin (mentum). Face presentation occurs in 0.1 to 0.2 percent of singleton deliveries. The causes of face presentation are numerous and often obscure. When the fetus is very large or the pelvis is contracted, there is a predisposition to extension of the fetal head. The pendulous abdomen of a grand multipara also promotes extension of the fetal head. In exceptional instances, enlargement of the neck because of goiter or cystic hygroma, or numerous coils of cord around the neck may cause extension. Anencephalic fetuses often present by the face because of absent development of the cranium.

Diagnosis The clinical diagnosis of a face presentation relies principally on the vaginal exam. The mouth, nose, and the malar prominences may be palpated. A face presentation may be confused with a breech presentation, particularly since breech is 20 times more common. The mouth may be mistaken for the anus, and the malar prominences mistaken for the ischial tuberosities. The anus and ischial tuberosities of a breech form a straight line, whereas the mouth and malar prominences of a face form a triangle. The exam may be very confusing due to edema of the facial structures, even for the most experienced practitioner. Imaging will confirm the diagnosis and rule out anencephaly.

Mechanism of Labor (slide 34) The key for successful delivery of a face is for the chin to end up under the symphysis, or be in mentum anterior position. Then, with further descent of the fetus, the cranial vault can sweep through the posterior pelvis and the head can be born by flexion. Although this mechanism does not present the most favorable diameter of the fetal head to the pelvis, if the fetus is not too large and the pelvis is adequate, spontaneous delivery can occur. If the chin rotates or remains posteriorly (slide 35) (mentum posterior) then there is no mechanism that allows the fetus to utilize the space in the posterior pelvis in the hollow of the sacrum, and delivery cannot occur.

G: Malpresentations, Malpositions, and Multiple Gestation 18 Management of Delivery Spontaneous vaginal delivery may occur sometimes with surprising ease. The fetus must rotate to a mentum anterior position. A persistent mentum posterior mandates a cesarean delivery. Attempts to manually convert a face to a vertex are outmoded and dangerous, as are attempts to rotate a mentum posterior to a mentum anterior. Forceps however, can be safely and successfully applied to a mentum anterior that is on the perineum. The vacuum extractor is absolutely contraindicated. Likewise, scalp electrode internal monitoring is contraindicated, to avoid injuring the face. Oxytocin augmentation should be used only with extreme caution, and is usually considered contraindicated. A large episiotomy may be recommended to accommodate the vertex coming through the posterior pelvis. Parents should be prepared for the dramatically bruised and edematous face of the infant, but recovery is prompt.

Brow Presentation In a brow presentation the portion of the fetal head between the orbital ridge and the anterior fontanel presents at the pelvic inlet. The fetal head is in an attitude between full flexion and full extension (or face). The presenting diameter of the fetal skull is the occipitomental, which is very unfavorable for delivery. Delivery of a persistent brow usually cannot take place unless the fetus is very small or the pelvis is very large. Brow presentation is found in 0.02 percent of singleton deliveries. The causes of this rare presentation are similar to those for face presentation. A brow presentation is usually unstable and will convert either to a face or a vertex presentation.

Diagnosis Diagnosis is by vaginal exam. The frontal sutures, anterior fontanel, orbital ridges, eyes, and root of the nose may be felt. Frequently the exam is confusing because of edema and unfamiliarity of the presenting features.

Mechanism and Management of Labor A persistent brow cannot deliver vaginally under normal conditions. If it converts to vertex or face, then delivery may occur according to their respective mechanisms. In the absence of conversion and progress in labor, cesarean delivery is required.

G: Malpresentations, Malpositions, and Multiple Gestation 19 Compound Presentation (slide 36) In a compound presentation an extremity, usually a hand, prolapses alongside the main presenting part, usually the head. Compound presentation occurs in 0.04 to 0.14 percent of deliveries. Often no cause is found. It is more common with premature infants and when the fetal presenting part does not completely occlude the pelvic inlet.

Diagnosis The diagnosis is usually readily made on vaginal exam. It is critically important to distinguish between a hand and a foot prolapsed alongside the head.

Management of Delivery As long as labor is progressing normally, no intervention is necessary. Most commonly the prolapsed limb will deliver spontaneously along with the head, or sometimes the fetus will retract its limb spontaneously. If the prolapsed arm appears to be impeding descent, it should be gently elevated upward and the head manipulated simultaneously downward.1 (Category C) Occasionally cesarean delivery will be necessary. The parents should be warned to expect bruising and edema of the prolapsed extremity.

Prolapse of the Umbilical Cord (slide 37) Prolapse of the umbilical cord is a true obstetrical emergency. The cord may become compressed or occluded between the presenting part of the fetus and the pelvic brim or sidewall resulting in asphyxia and death. The incidence of cord prolapse is 0.4 percent in vertex presentations, 0.5 percent in frank breeches, four to six percent in complete breeches, and 15 to 18 percent in footling breeches. (slide 38) Cord prolapse is most common when the fetus does not occlude the pelvic inlet well, as is the case with a footling breech. Other factors that may contribute to cord prolapse are prematurity, polyhydramnios, high presenting part, and a long cord. Occasionally the cause is iatrogenic, as for example when the membranes are ruptured with the presenting part high out of the pelvis. A gush of fluid may then wash the cord down into the vagina. On the other hand, the cord may have already been coiled beneath the fetal presenting part (occult cord prolapse) such that rupture of the membranes merely revealed the prolapse, but did not cause it. (slide 39) Rapid identification and response may truly save the life of the fetus. The management steps are: 1. Diagnose the cord prolapse by visual inspection or palpation on immediate vaginal exam. The cord may be found extruded from the vagina, coiled in the vagina, or wrapped across the presenting part. The only hint may be a severe variable deceleration or bradycardia following rupture of the membranes.

G: Malpresentations, Malpositions, and Multiple Gestation 20 2. Quickly assess the fetal status by monitoring or ultrasound. 3. Assess the dilation and status of labor. If the fetus can be delivered more quickly and safely per vagina than by cesarean delivery, then proceed immediately using forceps, vacuum or total breech extraction as appropriate. 4. If immediate vaginal delivery is not feasible then prepare for cesarean delivery. Elevate the presenting part out of the pelvis in an effort to protect the cord from occlusion. This may be performed by placing a hand in the vagina and forcefully (but carefully) elevating the presenting part upward. Alternatively, some success has been achieved by filling the bladder rapidly with 500 to 700 cc of saline. Tocolysis (e.g. terbutaline 0.25 mg subcutaneously) is helpful if the patient is in labor. Deep Trendelenburg position also is useful to add gravity to other efforts to elevate the fetus off the cord. The efficacy of these maneuvers can be measured by monitoring the fetus or palpating the cord. 5. Do not attempt the futile tactic of attempting to replace the cord in the uterus. 6. Perform an emergent cesarean delivery while continuing all efforts to hold the presenting part off the cord. 7. If delay is encountered, wrap the cord in warm wet packs. (slide 40) Prevention of cord prolapse is difficult but may be accomplished on occasion by identifying risk factors or by identifying a cord presentation by ultrasound. Artificial rupture of the membranes should not be done when the station is high. If artificial rupture of membranes is essential to manage a difficult obstetric situation, and the head is unengaged and high, the membranes can be needled under double set-up conditions. The same procedure can be used to rupture the membranes in cases of polyhydramnios. Patients in the latter stages of pregnancy who are at high risk for cord prolapse (e. g. footling breech, polyhydramnios) can be identified. They can be instructed to examine themselves for cord prolapse if their membranes rupture out of hospital. If a prolapse is identified, they should assume a deep knee-chest position and maintain the position even during transport to the hospital.

G: Malpresentations, Malpositions, and Multiple Gestation 21 Multiple Gestation (slide 41) Multiple gestation occurs in approximately 1.5 percent of births in the United States. Perinatal morbidity and mortality are increased two to five fold, largely due to prematurity. Congenital anomalies, IUGR, and intrapartum complications also contribute. Dizygosity (fraternal twinning) occurs in about two thirds of twin gestations, and is increased with age, parity, and certain familial and racial circumstances. Monozygosity (identical twinning) occurs in one third of twin gestations and is unrelated to any predisposing factors. Morbidity and mortality are higher in monozygotic twins. Maternal complications are common in multiple gestation. These include pregnancy induced hypertension, anemia, hyperemesis, abruption, placenta previa, postpartum hemorrhage, and increased operative delivery.

Diagnosis The routine use of ultrasound has greatly diminished the difficulties of diagnosing (slide 42) multiple gestation. Historical and physical findings suggestive of multiple gestation and indicating an ultrasound exam are: uterus larger than dates, hyperemesis gravidarum, early PIH, elevated maternal serum alpha feto-protein (MSAFP), suggestive palpatory or auscultory findings, polyhydramnios, ovulation induction, and family history.

Prenatal Management (slide 43) Several issues distinguish multiple gestations from singleton : 1. Prematurity is the greatest threat to multiple gestation infants, and prevention of prematurity is of the highest priority. Unfortunately, no preventive measures, including bed rest and tocolytics, have been clearly effective in preventing premature labor. The best approach appears to be attentive general support. 2. Compared to singletons, congenital anomalies and developmental defects are doubled in all twin pregnancies, and higher yet in monozygotic twin pregnancies. Ultrasound, and in some cases , should be considered. Monoamniotic twinning, which may be diagnosed by ultrasound, presents a very high risk situation due to cord entanglement. 3. Compared to singletons, pregnancy induced hypertension is doubled in twin gestations. Active surveillance and management are recommended. Iron deficiency is common, and iron supplementation is generally indicated. The possibility of intrauterine growth restriction (IUGR) and discordant growth requires surveillance. IUGR has been reported from 12 to 47 percent and discordancy from four to 23 percent, depending on the standard used (15 to 25 percent difference in weight using the larger twin as reference).

G: Malpresentations, Malpositions, and Multiple Gestation 22 Ultrasound exams every four weeks are recommended for early diagnosis. Intervention in the presence of significant discordancy is a complicated issue, and beyond the scope of this chapter. 4. Fetal death occurs in 0.5 to 6.8 percent of twin pregnancies. Conservative management of the surviving twin is indicated, at least until lung maturity is proven. The patient should be monitored for development of coagulopathy. 5. The incidence of placenta previa is increased in multiple gestations, possibly because of the larger surface area of the two . Certain complications of pregnancy do not seem to be increased in multiple gestations. These include diabetes, pyelonephritis, and third trimester bleeding.

Intrapartum management No obstetric situation presents a greater range of challenges than multiple gestation. Only the most skilled and confident obstetric providers should plan to attend twin deliveries without backup. Intrapartum complications include malpresentations, locking of twins, cord prolapse, abruption, non-reassuring fetal heart rate tracing, dysfunctional labor, and postpartum hemorrhage. Several of these complications can arise from the manner in which the twins present. Either fetus may be vertex, breech or in a transverse lie. Theoretically there are nine combinations of presentation of twins (slide 44) A and B, but for practical purposes there are three.

Presentation of Twins Twin A Twin B Occurrence (percent) Vertex Vertex 43 percent Vertex Non-vertex 38 percent Non-vertex NA 19 percent

Vertex-vertex presentations are the most common and least complicated. With appropriate monitoring and the capability to respond to an emergency, labor may be allowed to progress to vaginal delivery of both infants. Oxytocin induction or augmentation, epidural anesthesia, and other interventions are all acceptable with caution. The interval between deliveries is not critical as long as the second fetus is doing well, but oxytocin augmentation is often used when delay is encountered between deliveries. When twin A is vertex, but twin B is non-vertex, controversy exists as to the best mode of delivery. Although many practitioners advocate cesarean delivery, it is not always necessary in this situation. Vaginal delivery of twin B in the nonvertex presentation is a reasonable option for a neonate with an estimated weight

G: Malpresentations, Malpositions, and Multiple Gestation 23 greater than 1,500 gm as long as criteria for vaginal delivery of a singleton breech are met.19 Cesarean delivery of a second twin not presenting cephalically has yet to be demonstrated to improve neonatal outcome.20 (Category A) A policy of routine cesarean delivery should not be adopted without further controlled trials. (slide 45) When vaginal delivery is attempted, the crisis point occurs after the delivery of twin A, at which time the physician must determine the presentation of twin B (which may be different from its presentation before twin A was born). A combination of external exam, internal exam, and ultrasound may be used. Assuming twin B is breech or in a transverse lie, a decision must then be made whether to 1) attempt an external version to vertex; 2) deliver twin B as a breech; or 3) perform a cesarean delivery. The exact obstetric circumstances, the experience of the operator, condition of the fetus, state of mind of the mother, and the available resources are all factors in the decision. External cephalic version is frequently successful, easy, and safe, as the uterus is often very relaxed after delivery of twin A, and there is plenty of room for twin B to turn. Once the vertex has been placed over and guided into the inlet manually, the membranes can be ruptured or oxytocin augmentation given (or both) and a vertex delivery should ensue. A breech delivery is also a possibility for twin B. This may be inadvisable for very small fetuses, but macrosomia with difficult delivery is rarely a problem in the second twin. Breech delivery is a reasonable choice in the following circumstances: 1. When external version is unsuccessful or not attempted 2. When labor is strong and the second fetus presents with the breech deep in the pelvis, in which case external version is not likely to succeed and prompt delivery is anticipated 3. When emergencies such as cord prolapse or a non-reassuring FHR tracing occur, and a skilled operator is available to perform a breech extraction. Occasionally twin B presents as a transverse lie with the back up and the feet dangling towards the cervix. In this situation, a procedure known as internal podalic version may be appropriate. The operator grasps both feet firmly through the membranes and pulls the feet into the vagina. An assistant helps rotate the fetus into proper position abdominally. With the operator exerting steady downward traction on the feet to maintain the breech as the presenting part, the membranes are then ruptured. The delivery then proceeds as a breech. This is probably the most difficult and dangerous procedure permissible in modern obstetrics.

G: Malpresentations, Malpositions, and Multiple Gestation 24 Cesarean delivery may be required for a non-vertex twin B. Situations mandating Cesarean delivery include a non-reassuring fetal heart tracing, cord prolapse, abruption, or rupture of the membranes trapping the fetus in a transverse lie. A contributing problem occurs when the cervix “closes down” after twin A is born. These situations can arise suddenly, so resources for immediate cesarean delivery should be available. When twin A is non-vertex, cesarean delivery is generally required for safety. External cephalic version of a breech twin A is not technically feasible. When twin A is breech and twin B is vertex or transverse, locking or collision of the twins is a disastrous event. Cesarean delivery in multiple gestation presents anesthetic and surgical challenges due to the enlarged uterus, the exaggerated physiologic response to pregnancy, and the potential for exotic presentations of the fetuses. The necessity for a vertical incision in both skin and uterus is a special consideration when the twins are in unusual or entwined positions. Conjoining of twins is a rare problem beyond the scope of this chapter, but should always be considered if ultrasound shows twins “face to face” or “back to back.” Undiagnosed twins are rare in areas where ultrasound is frequently used. However, in the pre-ultrasound era, as many as 50 percent of twins were unsuspected until after delivery of twin A. Therefore, when no ultrasound has been performed, birth attendants should always be alert for this possibility. After delivery, postpartum hemorrhage is relatively common due to the overdistension of the uterus. Providers should be fully prepared with intravenous access, proper oxytocics, and readily available blood products. Neonatal resuscitation is often required due to prematurity or the many potential complications of multiple gestation. Not uncommonly, two infants need attention simultaneously. Adequate personnel and equipment must be available.

(slide 46) Summary There are six types of malpresentations. Some are common (occiput posterior presentation, breech) and some are rare (transverse lie, brow, face, compound presentation). Diagnosis is made by a combination of physical examination and imaging. A high index of suspicion is helpful in making the diagnosis. Each type of malpresentation has its complications. Providers should be alert not only for complications resulting from labor and delivery, but also for problems that may be etiologic for the malpresentation in the first place. Vaginal delivery may be considered for four of the six malpresentations: occiput posterior presentation, breech, face, and compound presentation. With occiput posterior presentation, the provider has several management choices for delivery. With breech, complex criteria determine if vaginal delivery can occur safely.

G: Malpresentations, Malpositions, and Multiple Gestation 25 External cephalic version can prevent breech presentation at term. A high degree of technical skill and judgment is required to deliver patients with malpresentations safely. Multiple gestation presents a wide variety of special challenges to the provider.

Summary of Recommendations Category A Women with breech presentation who meet standard criteria near term should be offered an attempted external cephalic version.9,10,12 Caesarean section for delivery of a second twin not presenting cephalically as yet has not identified improvement in neonatal outcome.20

Category B Thirty seven weeks appears to be the optimal gestational age for ECV.9,10 Cesarean delivery does not prevent all infant morbidity in breech presentation.14,15

Category C The conduct of labor and delivery with a persistent OP is not markedly different from that of the fetus in the occiput anterior position.1 In an OP rotation, the hand should be used which pronates during the rotation (like closing a book): left hand for ROP and right hand for LOP.4 Various exercises and positions have been tried in an attempt to turn a breech and no difference in outcome has been noted in either a postural management group or a control group.6,7 When performing ECV, facilities and personnel must be available for performing an immediate cesarean delivery.13 There is insufficient evidence to recommend routine tocolysis for ECV for multiparous patients.12 In a compound presentation, if the prolapsed arm appears to be impeding descent it should be gently elevated upward and the head manipulated simultaneously downward.1

G: Malpresentations, Malpositions, and Multiple Gestation 26 References 1. Cunningham, MacDonald, Gant, et al (eds). Williams Obstetrics, 20th Edition, 1997; Appleton & Lange, Stamford, CT, Chapter 18: Dystocia – Abnormal presentation, position, and development of the fetus. pp 448-449. (Level III) 2. Cruickshank DP. Malpresentations and Umbilical Cord Complications. In: Danforth's Obstetrics and Gynecology, Sixth edition, Scott JR, DiSaia PJ, Hammond CB, and Spellacy WN (eds); J.B Lippincott Company, 1990. (Level III) 3. Pearl ML, Roberts JM, Laros RK, and Hurd WW. Vaginal delivery from the persistent occiput posterior position. Journal of Reproductive Medicine 1993;38(12):955-960. (Level II-2) 4. Cunningham, MacDonald, Gant, et al (eds). Williams Obstetrics, 20th Edition, 1997; Appleton & Lange, Stamford, CT, Chapter 18: Dystocia – Abnormal presentation, position, and development of the fetus. pp 482-483. (Level III) 5. Scheer K, Nubar J: Variation of fetal presentation with gestational age. Am J Obstet Gynecol 1976;125:269. (Level III) 6. Hofmeyr GJ, Kulier R. Cephalic version by postural management for breech presentation (Cochrane Review). In: The Cochrane Library Issue 3, 1999. Oxford: Update Software. (Level I) 7. Smith C, Crowther C, Wilkinson C, Pridmore B, and Robinson J. Knee-chest postural management for breech at term: A randomized controlled trial. Birth 1999;26(2):71-75. (Level I) 8. Cunningham, MacDonald, Gant, et al (eds). Williams Obstetrics, 20th Edition, 1997; Appleton & Lange, Stamford, CT, Chapter 18, pp 442-443. (Level III) 9. Hofmeyr GJ, Kulier R. External cephalic version for breech presentation at term (Cochrane Review). In: The Cochrane Library, Issue 3, 1999. Oxford: Update Software. (Level I) 10. External Cephalic Version. ACOG Practice Bulletin, Feb. 2000; No.13:1-6. (Level III) 11. Flamm BL, Fried MW, Lonky NM and Saurenman Giles W. External cephalic version after previous cesarean delivery. Am J Obstet Gynecol 1991;165(2):370-372. (Level II-2) 12. Hofmeyr GJ. External cephalic version facilitation for breech presentation at term. The Cochrane Library, Issue 1, 2000. Oxford: Update Software. (Level I) 13. Zhang J, Watson AB, and Fortney JA. Efficacy of external cephalic version: A review. Obstetrics & Gynecology 1993;82(2):306-312. (Level III) 14. Danielian PJ, Wang J, and Hall MH. Long term outcome by method of delivery of fetuses in breech presentation at term: Population based follow up. Br Med J 1996;312:1451-1453. (Level II-2) 15. Hofmeyr GJ, Hannah ME. Planned Caesarean section for term breech delivery (Cochrane Review). In: The Cochrane Library, Issue 1, 2000. Oxford: Update Software. (Level I) 16. Zatuchni GI, and Andros GJ. Prognostic Index for vaginal delivery in breech presentation at term. Am J Obstet.Gynecol 1965;93:237. (Level III) 17. Hannah, M and others for the Term Breech Trial Collaborative Group. What is the best way to deliver a breech baby? Lancet 2000;356:1375-83. (Level I) 18. The Society of Obstetricians and Gynaecologists of Canada. SOGC Interim Position on Management of Term Breech. September 27, 2000. (Level III) 19. Special Problems of Multiple Gestation. ACOG Educational Bulletin No. 253, November 1998. page 807. (Level III) 20. Crowther CA: Caesarean delivery for the second twin (Cochrane Review). In: The Cochrane Library, Issue 1, 2000. Oxford: Update Software. (Level I)

G: Malpresentations, Malpositions, and Multiple Gestation 27 Planned Cesarean Delivery for Breech Presentation Malpresentations • Term Breech Trial (2000)

) Planned cesarean birth reduces Supplementary Provider perinatal/neonatal mortality and serious Course Slides neonatal morbidity compared to vaginal breech delivery • ACOG Position: “Planned vaginal delivery of a singleton term breech may no longer be appropriate”

1 2

Planned Cesarean Delivery for Breech Presentation

• Term Breech Trial 2-year follow-up (2004) ) Re-evaluated the combined endpoint of death or neurodevelopmental delay at 2 years ) Found no difference between planned cesarean and vaginal breech groups

• ALSO continues to teach vaginal breech delivery because unanticipated breech deliveries do occur

3

1 Malpresentations, Objectives Malpositions and • Define six types of malpresentations Malpositions and • List complications associated with various Multiple Gestation malpresentations Multiple Gestation • Discuss criteria for selection and management of vaginal delivery with malpresentation • Discuss delivery management of multiple gestation (optional) • Perform delivery of malpresentations using maternal-fetal mannequin 1 2

Definitions Methods of Diagnosis

• Lie • Leopold’s (abdominal palpation) )Relationship of long axis of fetus to mother • Vaginal exam )Longitudinal, transverse, oblique • Presentation • Imaging – ultrasound, flat plate of abdomen )Portion of fetus foremost in birth canal )Vertex, breech, face, brow, shoulder • Position )Reference point on presenting part )Examples: LOA / ROA / LOP

3 4

Fetal Head Diameters Asynclitism

Anterior Fontanel • Lateral flexion of fetal head • Sagittal suture not in midline Coronal Suture Posterior Fontanel • Normal in small degrees Occiptomental • Extreme degrees lead to dystocia diameter: 12.5cm • Major factor in forceps application

Subocciptobregmatic diameter: 9.5cm 5 6

1 Pelvic Types Occiput Posterior Gynecoid Anthropoid Platypelloid Android • “Back labor” • Asymmetric dilation, persistent anterior lip • Ease of palpation of anterior fontanel on vaginal exam • Palpation of ear

Round inlet Oval inlet (AP) Oval inlet Triangular inlet normal prominent (transverse) prominent spines

spines spines flat spines narrow forepelvis7 8

Mechanisms of OP Delivery

Manual Rotation of OP

Flex fetal head by placing a hand in the hollow of sacrum, behind the occiput

9 10

Vacuum Delivery of OP Forceps Delivery of OP

Note how vectors of force promote flexion with a posterior application

11 12

2 Breech Presentation Risk Factors for Breech

• Prematurity • High parity • Uterine anomalies • Pelvic tumors • Polyhydramnios, oligohydramnios • Fetal anomalies • Absolute CPD Frank Complete Footling • Previous breech 13 14

Prenatal Management Breech Exercises

• Seek a cause for the breech • Attempt maternal position exercises to turn breech Knee Chest Position • Attempt external cephalic version • Determine most favorable mode of delivery

Deep Trendelenburg

15 16

External Cephalic Version Contraindications to ECV Factors Associated with Success • Multiple pregnancy • Parity • Utero-placental insufficiency • Frank breech • Normal or increased amniotic fluid • Non-reassuring FHR tracing • Relaxed uterus • Uterine anomalies • Gestational age <37 weeks • Placenta previa • Tocolysis • Unexplained bleeding • Acoustic stimulation • Maternal medical conditions

17 18

3 Complications of ECV

• Fetal bradycardia, decelerations • Abruption Elevate • Fetal hemorrhage breech with suprapubic • Maternal hemorrhage hand • Knotted or entangled cord • Fetal mortality • Amniotic fluid embolus,

19 20

Now fetus in Push transverse lie breech into iliac fossa Ultrasound is used to Assistant monitor flexes head progress and heart rate

21 22

Fetus is past transverse Ultrasound Little effort confirmation required to of fetal guide head into presentation a vertex presentation

23 24

4 Vaginal Breech Contraindications Breech Delivery

• Unfavorable pelvis Most favorable diameter for breech is same as that of cephalic • Macrosomia Symphysis Symphysis • Severe prematurity • IUGR, placental insufficiency • Footling breech • Hyperextension of fetal head • Fetal anomalies • Nuchal arm Sacrum • PROM or non-progressive labor Sacrum • Lack of skills 25 Breech Cephalic 26

Vaginal Breech Delivery: Delivery of the Fetal Pelvis

• Hand gently supporting the emerging breech • Keep the sacrum anterior

27 Delivery of the Legs - Optional Maneuver 28

Delivery of the Gentle Traction Anterior Arm in a on Fetal Pelvis Vaginal Breech Extraction

29 30

5 MSV Maneuver And Suprapubic Pressure

Dűhrssen’s Incisions: Cutting the Cervix for an Entrapped Head

31 32

Neglected Shoulder Presentation With Arm Prolapse

Pathologic Retraction Ring Mechanism Bulging Lower of Mentum Uterine Segment Anterior Face Delivery

33 34

Mentum Posterior Face Compound Presentation - Presentation Vaginal Delivery Impossible

35 36

6

• Risk Factors ) Malpresentation, prematurity, polyhydramnios, high presenting part, long cord • Epidemiology Prolapsed Umbilical Cord in Presentation Incidence Footling Breech Vertex 0.4% Frank breech 0.5% Complete breech 4.0-6.0% Footling breech 15%-18% 37 38

Rapid Response to Prolapse Prevention of Prolapse

• Recognize non-reassuring tracing • Visually inspect / palpate cord to diagnose • Identify risk factors • Assess fetal status (FHTs, ultrasound) )Malpresentation, high presentation • Assess labor progress (dilation, station) )Patient education re: membrane rupture at home • Do not attempt to replace cord • No AROM when station high • Hold presenting part off cord )May “needle” membranes under double set-up ) Foley catheter ) Position change (Trendelenburg, Knee-chest) • Tocolysis

39 40

Multiple Gestation Diagnosis of Multiple Gestation

• Occurs in 1.5% of U.S. births • Ovulation induction • 2-5 X higher perinatal mortality • Family history • Maternal complications common • Hyperemesis

)HTN, anemia, hyperemesis, abruption, previa, • Uterine size > dates PPH, operative delivery • Early PIH • Dizygosity (fraternal) = 2/3 • Elevated MSAFP )Increases with age, parity, familial factors • Auscultation of >1 fetal heart beat • Monozygosity (identical) =1/3 • Polyhydramnios 41 42

7 Associated Complications Presentation of Twins

• Prematurity • Congenital anomalies • Pregnancy-induced hypertension • Placenta previa • Fetal death: 0.5%-6.8%

Vertex-Vertex Vertex-NonVertex NonVertex 43% 38% (twin A) 19% 43 44

Delivering Twin B Summary

• Attempt internal podalic version • Six types of malpresentations • Breech delivery is reasonable choice when: • Diagnosis by physical exam and imaging )External version unsuccessful or not attempted • Be alert to etiologic associations )Strong labor and Baby B deep in pelvis • Be alert to potential complications )Cord prolapse or nonreassuring FHR tracing • Vaginal delivery may be considered for OP, breech, face and compound presentation

45 46

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