Vaginal Bleeding in Late Pregnancy Objectives Identify major causes of vaginal bleeding in the second half of pregnancy Describe a systematic approach to identifying the cause of bleeding Describe specific treatment options based on diagnosis Causes of Late Pregnancy Bleeding Placenta Previa Abruption Life-Threatening Ruptured vasa previa Uterine scar disruption Cervical polyp Bloody show Cervicitis or cervical ectropion Vaginal trauma Cervical cancer Prevalence of Placenta Previa Occurs in 1/200 pregnancies that reach 3rd trimester Low-lying placenta seen in 50% of ultrasound scans at 16-20 weeks 90% will have normal implantation when scan repeated at >30 weeks No proven benefit to routine screening ultrasound for this diagnosis Risk Factors for Placenta Previa Previous cesarean delivery Previous uterine instrumentation High parity Advanced maternal age Smoking Multiple gestation Morbidity with Placenta Previa Maternal hemorrhage Operative delivery complications Transfusion Placenta accreta, increta, or percreta Prematurity Patient History – Placenta Previa Painless bleeding 2nd or 3rd trimester, or at term Often following intercourse May have preterm contractions “Sentinel bleed” Physical Exam – Placenta Previa Vital signs Assess fundal height Fetal lie Estimated fetal weight (Leopold) Presence of fetal heart tones Gentle speculum exam NO digital vaginal exam unless placental location known Laboratory – Placenta Previa Hematocrit or complete blood count Blood type and Rh Coagulation tests While waiting – serum clot tube taped to wall Ultrasound – Placenta Previa Can confirm diagnosis Full bladder can create false appearance of anterior previa Presenting part may overshadow posterior previa Transvaginal scan can locate placental edge and internal os Treatment – Placenta Previa With no active bleeding Expectant management No intercourse, digital exams With late pregnancy bleeding Assess overall status, circulatory stability Full dose Rhogam if Rh- Consider maternal transfer if premature May need corticosteroids, tocolysis, amniocentesis Double Set-Up Exam Appropriate only in marginal previa with vertex presentation Palpation of placental edge and fetal head with set up for immediate surgery Cesarean delivery under regional anesthesia if: Complete previa Fetal head not engaged Non-reassuring tracing Brisk or persistent bleeding Mature fetus Placental Abruption Premature separation of placenta from uterine wall Partial or complete “Marginal sinus separation” or “marginal sinus rupture” Bleeding, but abnormal implantation or abruption never established Epidemiology of Abruption Occurs in 1-2% of pregnancies Risk factors Hypertensive diseases of pregnancy Smoking or substance abuse (e.g. cocaine) Trauma Overdistention of the uterus History of previous abruption Unexplained elevation of MSAFP Placental insufficiency Maternal thrombophilia/metabolic abnormalities Abruption and Trauma Can occur with blunt abdominal trauma and rapid deceleration without direct trauma Complications include prematurity, growth restriction, stillbirth Fetal evaluation after trauma Increased use of FHR monitoring may decrease mortality Bleeding from Abruption Externalized hemorrhage Bloody amniotic fluid Retroplacental clot 20% occult “uteroplacental apoplexy” or “Couvelaire” uterus Look for consumptive coagulopathy Patient History - Abruption Pain = hallmark symptom Varies from mild cramping to severe pain Back pain – think posterior abruption Bleeding May not reflect amount of blood loss Differentiate from exuberant bloody show Trauma Other risk factors (e.g. hypertension) Membrane rupture Physical Exam - Abruption Signs of circulatory instability Mild tachycardia normal Signs and symptoms of shock represent >30% blood loss Maternal abdomen Fundal height Leopold’s: estimated fetal weight, fetal lie Location of tenderness Tetanic contractions Ultrasound - Abruption Abruption is a clinical diagnosis! Placental location and appearance Retroplacental echolucency Abnormal thickening of placenta “Torn” edge of placenta Fetal lie Estimated fetal weight Laboratory - Abruption Complete blood count Type and Rh Coagulation tests + “Clot test” Kleihauer-Betke not diagnostic, but useful to determine Rhogam dose Preeclampsia labs, if indicated Consider urine drug screen Sher’s Classification - Abruption mild, often retroplacental Grade I clot identified at delivery tense, tender abdomen and Grade II live fetus Grade III with fetal demise III A - without coagulopathy (2/3) III B - with coagulopathy (1/3) Treatment – Grade II Abruption Assess fetal and maternal stability Amniotomy IUPC to detect elevated uterine tone Expeditious operative or vaginal delivery Maintain urine output > 30 cc/hr and hematocrit > 30% Prepare for neonatal resuscitation Treatment – Grade III Abruption Assess mother for hemodynamic and coagulation status Vigorous replacement of fluid and blood products Vaginal delivery preferred, unless severe hemorrhage Coagulopathy with Abruption Occurs in 1/3 of Grade III abruption Usually not seen if live fetus Etiologies: consumption, DIC Administer platelets, FFP Give Factor VIII if severe Epidemiology of Uterine Rupture Occult dehiscence vs. symptomatic rupture 0.03 – 0.08% of all women 0.3 – 1.7% of women with uterine scar Previous cesarean incision most common reason for scar disruption Other causes: previous uterine curettage or perforation, inappropriate oxytocin usage, trauma Risk Factors – Uterine Rupture Previous uterine surgery Adenomyosis Congenital uterine Fetal anomaly anomaly Uterine overdistension Vigorous uterine pressure Gestational trophoblastic Difficult placental neoplasia removal Placenta increta or percreta Morbidity with Uterine Rupture Maternal Hemorrhage with anemia Bladder rupture Hysterectomy Maternal death Fetal Respiratory distress Hypoxia Acidemia Neonatal death Patient History – Uterine Rupture Vaginal bleeding Pain Cessation of contractions Absence of FHR Loss of station Palpable fetal parts through maternal abdomen Profound maternal tachycardia and hypotension Uterine Rupture Sudden deterioration of FHR pattern is most frequent finding Placenta may play a role in uterine rupture Transvaginal ultrasound to evaluate uterine wall MRI to confirm possible placenta accreta Treatment Asymptomatic scar disruption – expectant management Symptomatic rupture – emergent cesarean delivery Vasa Previa Rarest cause of hemorrhage Onset with membrane rupture Blood loss is fetal, with 50% mortality Seen with low-lying placenta, velamentous insertion of the cord or succenturiate lobe Antepartum diagnosis Amnioscopy Color doppler ultrasound Palpate vessels during vaginal examination Diagnostic Tests – Vasa Previa Apt test – based on colorimetric response of fetal hemoglobin Wright stain of vaginal blood – for nucleated RBCs Kleihauer-Betke test – 2 hours delay prohibits its use Management – Vasa Previa Immediate cesarean delivery if fetal heart rate is non- reassuring Administer normal saline 10 – 20 cc/kg bolus to newborn, if found to be in shock after delivery Summary Late pregnancy bleeding may herald diagnoses with significant morbidity/mortality Determining diagnosis important, as treatment dependent on cause Avoid vaginal exam when placental location not known Vasa previa SECOND AND THIRD TRIMESTER BLEEDING — Vaginal bleeding is less common in the second and third trimesters. The major causes of bleeding at these times are: Bloody show associated with cervical insufficiency or labor Placenta previa Abruptio placenta Uterine rupture Vasa previa Placenta previa INTRODUCTION — Placenta previa refers to the presence of placental tissue that extends over or lies proximate to the internal cervical os. Sequelae include the potential for severe bleeding and preterm birth, as well as the need for cesarean delivery. Placenta previa should be suspected in any woman beyond 20 weeks of gestation who presents with painless vaginal bleeding. For women who have not had a second trimester ultrasound examination, antepartum bleeding after 20 weeks of gestation should prompt sonographic determination of placental location before digital vaginal examination is performed because palpation of the placenta can cause severe hemorrhage. PREVALENCE AND RISK FACTORS Purported risk factors, some of which are interdependent, include [ 2-12 ]: Previous placenta previa Previous cesarean delivery Multiple gestation Multiparity Advanced maternal age Infertility treatment Previous abortion Previous intrauterine surgical procedure Maternal smoking Maternal cocaine use Male fetus Non-white race PATHOGENESIS — The pathogenesis of placenta previa is unknown. One hypothesis is that the presence of areas of suboptimal endometrium in the upper uterine cavity due to previous surgery or pregnancies promotes implantation of trophoblast in, or unidirectional growth of trophoblast toward, the lower uterine cavity [ 1,2,13 ]. Another hypothesis is that a particularly large placental surface area, as in multiple gestation or in response to reduced uteroplacental perfusion, increases the likelihood that the placenta will cover or encroach upon the cervical os. PATHOPHYSIOLOGY — Placental bleeding is thought to occur when gradual changes in the cervix and lower uterine segment apply shearing forces to the inelastic placental attachment site, resulting in partial detachment. Vaginal examination or coitus can also disrupt