DOI: 10.1111/1471-0528.12989 www.bjog.org

Intrapartum monitoring with and ST-waveform analysis in breech presentation: an observational study

J Kessler,a,b D Moster,c,d,e S Albrechtsena,b a Department of and Gynaecology, Haukeland University Hospital, Bergen, Norway b Department of Clinical Science, Research Group for , Fetal Development and Birth, University of Bergen, Bergen, Norway c Department of Health Registries, Norwegian Institute of Public Health, Bergen, Norway d Department of Paediatrics, Haukeland University Hospital, Bergen, Norway e Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway Correspondence: Dr J Kessler, Department of Obstetrics and Gynaecology, Haukeland University Hospital, 5021 Bergen, Norway. Email: [email protected]

Accepted 29 May 2014. Published Online 18 July 2014.

Objective To determine the electrocardiographic performance and Results Breech presentation occurred in 750 of 23 219 (3.2%) neonatal outcome of with breech presentation and deliveries, 625 (83%) of which were selected for vaginal delivery. planned vaginal delivery monitored with ST-waveform analysis Intrapartum monitoring by STAN was performed in 433 (69%). (STAN). Compared with vertex presentations, fetuses in breech presentation had a lower risk of baseline T/QRS rise during Design Prospective observational study. labour [odds ratio (OR) = 0.7, 95% confidence interval (95% Setting University hospital, Norway; 2004–2008. CI) = 0.7–0.9, P = 0.003] and a higher risk for intervention as a result of preterminal cardiotocogram (OR = 2.9, 95% CI = 1.6– Population Singleton pregnancies with a above 5.9, P = 0.001). The risks of perinatal mortality (OR = 1.8, 95% 35 + 6 weeks, breech presentation, selected for vaginal delivery CI = 0.2–15, P = 0.6), cord metabolic acidosis (OR = 0.8, 95% and monitored with STAN. CI = 0.2–3.2, P = 0.7) and moderate or severe neonatal Methods Common clinical guidelines for STAN monitoring were encephalopathy (OR = 1.8, 95% CI = 0.5–6.2, P = 0.3) did not used. An experienced neonatologist graded the symptoms of differ significantly between breech and vertex deliveries. neonatal encephalopathy. The outcome was compared with Conclusion STAN can be used for the surveillance of breech STAN-monitored high-risk deliveries in a vertex presentation presentations selected for vaginal delivery with an acceptable (n = 5569) using logistic regression analysis. neonatal outcome. The electrocardiogram (ECG) pattern during Main outcome measure Frequency of ST events, indications of labour varies with the fetal presentation. intervention for fetal distress, and neonatal morbidity and Keywords Breech presentation, fetal electrocardiogram (ECG), mortality. intrapartum monitoring, neonatal outcome, ST-waveform analysis.

Please cite this paper as: Kessler J, Moster D, Albrechtsen S. Intrapartum monitoring with cardiotocography and ST-waveform analysis in breech presentation: an observational study. BJOG 2014; DOI: 10.1111/1471-0528.12989.

mode of delivery.6 In contrast with the recommendations Introduction – of the Cochrane review,7 several national guidelines8 10 still The Term Breech Trial (TBT) revealed an increased mortal- support the option of vaginal delivery for breech presenta- ity in participants randomised to planned vaginal delivery tion at term. relative to elective .1 This study resulted in Cardiotocography (CTG), which is the basic method of changes to the management of breech presentation at term, surveillance of high-risk labour, is hampered by a high sen- with elective caesarean delivery being recommended in sitivity and low specificity for the detection of intrapartum – most countries.2 4 The TBT has since been criticised for hypoxia. As a result of the risk of cord compression and methodological flaws,5 and long-term follow-up of the cord prolapse in breech presentations, continuous elec- infants has not confirmed that the outcome differs with the tronic fetal monitoring is essential in order to reveal fetal

ª 2014 Royal College of Obstetricians and Gynaecologists 1 Kessler et al. hypoxia in a timely manner. The use of ST-waveform Piper’s forceps were used liberally for the delivery of the af- analysis (STAN) of the fetal electrocardiogram (ECG) as an tercoming head. A paediatrician was present at delivery. In adjunct to CTG has been found to reduce the frequency of cases with ruptured membranes, a fetal electrode was vaginal operative deliveries, the necessity of fetal blood attached at the onset of active labour. If the CTG was nor- sampling and the frequency of neonate transferral to the mal, the fetal membranes were kept intact. Amniotomy was neonatal intensive care unit (NICU).11 The largest rando- not performed unless CTG abnormalities occurred. The mised controlled trials have also demonstrated a decreased fetal electrode was most often attached to the fetal buttock, frequency of cord metabolic acidosis.12,13 in some cases to the foot. In order to enable an ECG analy- Despite being a common indication for electronic fetal sis analogous to that for , the recorded monitoring, breech presentation was an exclusion criterion ECG had to be mirror imaged by activation of the ‘Breech in all but one14 of the five randomised trials on CTG and mode’ in the monitoring device. The diagnosis and inter- STAN.12,13,15,16 A total of 55 cases with breech presentation vention in cases of suspected intrapartum hypoxia were were randomised in the Plymouth study,14 30 of these to based on the clinical guidelines for monitoring with CTG CTG and STAN. Thus, the evidence from randomised trials and STAN.18 CTG classification was conducted according supporting the use of the method in breech presentation is to the International Federation of Gynaecology and Obstet- almost negligible. The aim of the present study was there- rics.19 CTG abnormalities were then related to the occur- fore to investigate the fetal ECG waveform pattern and to rence of ST events (Table 1) to determine whether or not evaluate the neonatal outcome of pregnancies with breech to intervene. presentation selected for vaginal delivery, monitored with If hypoxia is indicated during the first stage of labour, STAN. clinical guidelines18 recommend intrauterine resuscitation as the first measure and, if not successful, an operative Materials and methods intervention should be performed and delivery accom- plished within 20 minutes. Immediate delivery is warranted This was a prospective observational study of all singleton if hypoxia is indicated during the second stage.18 pregnancies with a gestational age above 35 + 6 weeks with An adverse neonatal outcome was defined as follows: a planned vaginal delivery that were monitored by STAN perinatal mortality, cord metabolic acidosis [arterial pH between 1 January 2004 and 31 December 2008. STAN mon- (pHartery) < 7.05 and base deficit in the extracellular fluid 20,21 itoring was restricted to high-risk deliveries as defined by (BDecf) > 12 mmol/l ], cord acidosis at delivery [either 17 local guidelines. The study protocol was assessed by the moderate (pHartery < 7.15, <10th percentile) or severe 22 regional ethics committee (REK Vest, 129.08) and defined as (pHartery < 7.05, <2.5th percentile) ], a 5-minute Apgar a quality improvement project which, according to Norwe- score of <7, transfer to the NICU, and moderate or severe gian law on medical research, does not require written neonatal encephalopathy (NE). NE was graded according patient consent for their involvement. The study population to Sarnat and Sarnat23 by an experienced neonatologist, as consisted of pregnancies with a fetus in breech presentation; described elsewhere.17 those with cephalic presentation served as a reference. The The occurrence of ST interval changes, the risk of ST sig- overall results on the maternal and neonatal outcome of the nal disturbance and the risk of adverse outcome were com- study population have been published elsewhere.17 pared with those for a reference population using logistic Women with a fetus in breech presentation were selected regression analysis. The characteristics of the study and to undergo a planned vaginal delivery according to the fol- background were evaluated using Pearson’s chi-squared test lowing local guidelines: 1 The estimated fetal weight did not exceed 4500 g (indi- vidual assessment between 4000 and 4500 g according to Table 1. Clinical guidelines for the use of cardiotocography (CTG) pelvic size and obstetric history). and ST-waveform analysis; recommendations for intervention 2 Computed tomography (CT) pelvimetry was performed according to CTG abnormalities and ST events ≥ ≥ [conjugata vera 11.5 cm, sum of outlet 32.5 cm Intermediary Abnormal Preterminal (sagittal outlet + intertuberous + interspinous diame- CTG CTG CTG ters)] in nulliparous women or those with a large discor- dance between previous birthweight and estimated fetal Episodic T/QRS rise >0.15 >0.10 Immediate weight in the current pregnancy. delivery Epidural anaesthesia was advised for all women in the Baseline T/QRS rise >0.10 >0.05 study population. All deliveries were performed by, or Biphasic ST Three biphasic Two biphasic under the supervision of, a senior consultant. The shoul- events events ders and arms were delivered by Løvset’s manoeuvre.

2 ª 2014 Royal College of Obstetricians and Gynaecologists Intrapartum monitoring and breech presentation and Student’s t-test. The level of statistical significance for The distribution of indications to intervene in cases of all statistical tests was set at P < 0.05. suspected hypoxia, as given by the STAN clinical guidelines, also varied with the type of fetal presentation. Interventions Results as a result of baseline T/QRS rise occurred less often in breech presentation, whereas hypoxia was more frequently A breech presentation occurred in 750 of 23 219 (3.4%) indicated by a preterminal CTG. The distribution of indica- deliveries. Among these, 625 (83%) were selected for tions for intervention was not influenced by birthweight, attempted vaginal delivery, 433 (69%) of which were mon- gestational age at delivery or fetal sex (Table 3). itored with STAN. Pregnancies with breech presentation The indicators of severe adverse neonatal outcome (cord were characterised by predominantly nulliparous women, metabolic acidosis, perinatal mortality, and moderate or who were less likely to have their labour induced severe NE) did not differ significantly between the breech (Table 2). This was partly a result of a lower frequency of and cephalic presentations (Table 4). However, there was pregnancy complications (Table 2). Although 78% of the an increased frequency of moderate or severe cord acidosis women selected to a trial of labour had a vaginal delivery, and low 5-minute Apgar score in breech presentations the frequency of emergency caesarean section was signifi- (Table 4). This was not reflected in an increased need for cantly higher for breech than for cephalic presentations intensive care: the transfer to NICU and the proportion of (Table 2). neonates with a prolonged stay at NICU (>3 days) did not The ECG signal quality in fetuses with a breech presen- differ significantly between breech and cephalic presenta- tation differed from that of the reference population, tions (Table 4). exhibiting a higher proportion of recordings with a In all cases with moderate or severe NE, the delivery of non-interpretable ST signal (Table 3). Fetal presentation the shoulders, arms and aftercoming head was described also influenced the pattern of ST interval changes during as uncomplicated. Nevertheless, the neonates remained labour. Significant ST changes were less common among depressed despite immediate resuscitation (Table 5). the breech presentations. Furthermore, these fetuses were Autopsy findings in case 1 (reactive gliosis in both hippo- less likely to have a baseline T/QRS rise, but were more campi) indicated a possible prenatal brain damage. Bilat- likely to exhibit a biphasic ST waveform compared with eral pneumothorax was diagnosed after the initial the reference (Table 3). However, the latter difference resuscitation in case 3. None of the cases with moderate between cephalic and breech presentations was nullified NE showed any signs of cerebral palsy when followed up after adjustment for birthweight, gestational age at deliv- by a child neurologist. ery and fetal sex (Table 3). Discussion Main findings Table 2. Basic characteristics, occurrence of pregnancy The present prospective observational study demonstrated complications and mode of delivery according to fetal presentation. the feasibility of using STAN technology to monitor vaginal Data are means Æ standard deviation (SD) or n (%) values breech deliveries. The pattern of ST interval changes during labour was different between breech and cephalic presenta- Breech Vertex P (n = 433) (n = 5577) tions. The frequency of severe adverse neonatal outcome did not differ significantly between breech presentation and high-risk vertex deliveries monitored by STAN; however, Maternal age (years) 29.8 Æ 4.8 29.6 Æ 5.2 0.6 Nulliparous 290 (67%) 3335 (60%) 0.002 this finding must be interpreted with caution because of Pregnancy complications the small sample of the study. Diabetes mellitus 1 (0.2%) 66 (1.2%) 0.09 Gestational diabetes 4 (1%) 151 (3%) 0.01 Strengths Pre-eclampsia 17 (4%) 510 (9%) <0.001 The delivery of a significant number of babies in breech < Induced labour 66 (15%) 1883 (34%) 0.001 presentation allowed the medical staff to become experi- Gestational 280 Æ 10 284 Æ 10 <0.001 enced at such deliveries, and encouraged the development age at delivery (days) Post-term delivery 44 (10%) 1240 (22%) <0.001 of effective teamwork. The uniform management, thorough Birthweight (g) 3385 Æ 531 3638 Æ 504 <0.001 evaluation of intrapartum monitoring and neonatal out- Mode of delivery come represent strengths of the present study. Further- Vaginal delivery 336 (78%) 4701 (84%) more, the sample in this study was considerably larger than Caesarean section 97 (22%) 876 (16%) <0.001 those in previous investigations on fetal monitoring in breech presentation.

ª 2014 Royal College of Obstetricians and Gynaecologists 3 Kessler et al.

Table 3. Electrocardiogram (ECG) signal quality, ST interval changes and indication for intervention as a result of hypoxia according to fetal presentation

Breech (n = 433) Cephalic (n = 5577) OR (95% CI) OR (95% CI)* n (%) n (%)

ECG signal quality No interpretable ST 23 (5.3) 181 (3.2) 1.7 (1.1–2.6) Impaired signal in first stage 42 (9.7) 518 (9.3) 1.0 (0.8–1.5) Impaired signal in second stage 58 (13.4) 777 (14.0) 1.0 (0.7–1.3) ST interval changes Any ST event 200 (46.2) 2897 (51.9) 0.8 (0.6–0.9) 0.8 (0.7–0.9) Baseline T/QRS rise 168 (38.8) 2621 (47.0) 0.7 (0.6–0.9) 0.7 (0.6–0.9) Episodic T/QRS rise 49 (11.3) 535 (9.5) 1.2 (0.9–1.6) 1.2 (0.9–1.6) Biphasic ST 43 (9.9) 391 (7.0) 1.5 (1.1–2.0) 1.3 (0.9–1.8) Indication of hypoxia n = 77 n = 1052 Baseline T/QRS rise 36 (46.8) 684 (65.0) 0.5 (0.3–0.8) 0.6 (0.4–0.8) Episodic T/QRS rise 8 (10.3) 120 (11.4) 0.9 (0.4–1.9) 0.7 (0.4–1.5) Biphasic ST 13 (16.9) 115 (10.9) 1.6 (0.9–3.1) 1.2 (0.6–2.1) Preterminal cardiotocography (CTG) 13 (16.9) 51 (4.9) 4.0 (2.1–7.7) 2.9 (1.6–5.9) Abnormal CTG in second stage 7 (9.1) 80 (7.6) 1.2 (0.5–2.7) 1.1 (0.5–2.3)

*Adjusted for birthweight, gestational age at delivery and fetal sex.

Limitations late first and second stages of labour. A threshold for inter- The observational design of the present study prevents any vention of pH < 7.15 has been suggested based on 30 cases, direct comparison with other monitoring techniques (e.g. as this cut-off is predictive of a 1-minute Apgar score of fetal blood sampling). A major limitation of this study is <4.30 Another study that included 10 cases revealed strong the size of the study population, which limits the ability to correlations between pH values obtained from the fetal draw conclusions on rare, serious, adverse events. Further- buttock within 15 minutes before delivery and umbilical more, cases with cord acidaemia could have been missed as arterial and venous pH at delivery.31 However, the useful- cord acid–base samples were not available in all cases. The ness of fetal blood sampling as an additional method in selection of the reference population can also be ques- fetal monitoring has only been tested in one randomised tioned. Vertex deliveries monitored by STAN were chosen study.32 Breech presentation was an exclusion criterion in in order to elaborate upon the potential differences in ECG that study, and the results did not show any improvements waveform analysis related to fetal presentation. in neonatal and maternal outcomes. The introduction of lactate measurement in fetal blood sampling resulted in a Interpretation higher success rate in sampling and assessment than pH The proportion of pregnancies with breech presentation measurement, without any improvement in neonatal out- selected for vaginal delivery was higher than in previously come.33 No reference ranges for lactate samples taken from published data from our own institution24 and from other the fetal buttock have been published. recent observational studies from Norway,25 Finland26 and Fetal blood sampling provides only isolated temporal Belgium/France (the PREMODA study).10 This can be measurements, whereas analysis of the fetal ECG gives con- partly explained by a reduction in the use of pelvimetry tinuous information on the fetal cardiac metabolism.34 An during the study period. The proportion of women who optimal signal quality is necessary for the timed detection had a vaginal delivery in the present study did not differ of significant ST changes.18 The ECG signal quality has not from those in the aforementioned studies. been assessed previously in relation to fetal presentation. Most guidelines on the intrapartum management of a The higher proportion of recordings with no interpretable vaginal breech delivery9,10,27 include electronic fetal moni- ST signal in breech presentations in the present study could toring as a prerequisite because of the increased risk of be a result of the heart being further from the buttock than cord prolapse28 and cord compression.29 However, there from the head, spatial differences in the conductive proper- has been little research on methods of fetal monitoring ties of the body35 or the greater difficulty of applying the other than CTG during vaginal breech deliveries. Some fetal electrode to the fetal buttock, resulting in less stable authors have advocated fetal blood sampling during the signal conduction.

4 ª 2014 Royal College of Obstetricians and Gynaecologists Intrapartum monitoring and breech presentation

Table 4. Neonatal outcome according to fetal presentation

Breech (n = 433) Cephalic (n = 5577) OR (95% CI) P n (%) Mean Æ SD n (%) Mean Æ SD

Mortality Intrapartum 0 1 Neonatal 1 6 Perinatal 1 (0.2) 7 (0.1) 1.8 (0.2–15) 5-minutes Apgar score < 7 19 (4.3) 108 (1.9) 2.3 (1.4–3.8) Transfer to NICU 25 (5.7) 452 (8.1) 0.7 (0.5–1.1) NICU stay > 3 days 11 (2.5) 123 (2.2) 1.2 (0.6–1.2) Neonatal encephalopathy Mild 4 (0.9) 38 (0.7) Moderate 2 (0.4) 17 (0.3) Severe 1 (0.2) 4 (0.1) 1.8 (0.5–6.2) Cord acid base* Artery pH 7.19 Æ 0.09 7.23 Æ 0.08 <0.001

pCO2 (kPa) 8.6 Æ 1.8 7.5 Æ 1.4 <0.001

BDecf (mmol/l) 3.1 Æ 3.2 3.3 Æ 3.0 0.3

pO2 (kPa) 1.6 Æ 0.8 2.0 Æ 0.9 <0.001 Vein pH 7.29 Æ 0.08 7.31 Æ 0.07 <0.001

pCO2 (kPa) 6.0 Æ 1.2 5.7 Æ 1.1 <0.001

BDecf (mmol/l) 4.1 Æ 2.6 4.4 Æ 2.7 0.03

pO2 (kPa) 3.3 Æ 0.9 3.4 Æ 0.9 0.2 Cord metabolic acidosis 2 (0.6) 35 (0.7) 0.8 (0.2–3.2) Cord artery pH < 7.15 90 (25.6) 598 (12.5) 2.4 (1.9–3.1) Cord artery pH < 7.05 23 (6.6) 123 (2.6) 2.7 (1.6–4.2)

BDecf (mmol/l) > 12 3 (0.9) 44 (0.9) 0.9 (0.3–3.0)

BDecf, base deficit in the extracellular fluid; CI, confidence interval; NICU, neonatal intensive care unit; OR, odds ratio; pCO2, partial pressure of

carbon dioxide; pO2, partial pressure of oxygen. *Arterial samples available in n = 351 breech deliveries and n = 4786 vertex deliveries; venous samples available in n = 371 breech deliveries and n = 4892 vertex deliveries.

The different pattern of ST events in breech presenta- perceptions in humans is higher in the face than in the tions could be caused by differences in birthweight and ges- lower extremities and buttocks.39 As a consequence, the tational age at delivery (Table 2). Prematurity and low mechanical forces affecting the presenting part may result birthweight have previously been shown to be associated in higher levels of fetal arousal when applied to the fetal with a higher density of ST events in general, and biphasic skull, eyes and face relative to the feet and buttocks, which ST waveform in particular.36 The latter is also more preva- could explain the different patterns of ST interval changes lent among male fetuses.36 In the present study, adjustment between breech and cephalic presentations. for gestational age at delivery removed differences in the CTG remains the basic method in STAN monitoring. occurrence of biphasic ST waveforms. However, the associ- Early research on the changes in fetal heart rate that occur ation between breech presentation and a decreased propor- during breech delivery has highlighted the frequent occur- tion of cases with baseline T/QRS rise remained significant rence of variable and/or late decelerations being the result after this adjustment. ST interval changes not only evolve of repetitive cord compression, and their significance for as a result of hypoxia; a T/QRS rise is observed in one-half neonatal outcome.29 Decreased variability was present in of cases36 as a result of fetal arousal caused by physiological eight of 42 cases (19%), and all but two had a 1-minute sympathetic stimulation during labour.37 The effect of a Apgar score of <5 or the need for respiratory support.40 In given external stimulus may depend on fetal presentation: contrast, there are no published data on the prevalence of it has been found that the response to vibroacoustic stimu- preterminal CTG relative to fetal presentation. The present lation close to term is lower in breech than in cephalic pre- study found that a preterminal CTG as a primary indicator sentations.38 Furthermore, the sensitivity of somatosensory of hypoxia was more common in breech than in cephalic

ª 2014 Royal College of Obstetricians and Gynaecologists 5 Kessler et al.

influenced the ability of that fetus to tolerate peripartum Table 5. Cases with moderate and severe neonatal encephalopathy asphyxia. Delayed intervention was present in one-third of Case 1 Case 2 Case 3 cases with moderate or severe NE, which is in line with previous findings in a high-risk population.17 Gestational age (weeks) 40 + 342+ 140+ 6 Mode of delivery VD VD VD Conclusions Birthweight (g) 3240 3640 3160 Apgar score at 1/5 minutes 3/2 1/5 1/1 STAN monitoring is technically feasible during vaginal Cord acid base breech delivery, with an acceptable neonatal outcome. The Artery differential pattern of ST interval changes in breech presen- pH/BDecf (mmol/l) – 7.04/9.2 7.12/4.1 Vein tation may prompt a further refinement of clinical guide-

pH/BDecf (mmol/l) 7.24/5.2 7.16/10.9 – lines on STAN monitoring. Indication of hypoxia – Biphasic ST – Time indication– – 167 – Disclosure of interests delivery*** (min) JK received a lecture fee from Neoventa Medical, Mølndal, Neonatal encephalopathy Severe Moderate Moderate Sweden on one occasion. SA and DM do not have any Hypothermia Yes No* Yes Survival No Yes Yes conflicts of interest. Cerebral palsy** – No No Contribution to authorship BDecf, base deficit in the extracellular fluid; VD, vaginal breech JK collected and analysed the data, and wrote the manu- delivery. *Born before hypothermia was established as treatment at the local script. SA collected data and revised the manuscript. DM neonatal intensive care unit. evaluated the medical records of neonates transferred to **During a 4-year follow-up. the NICU and revised the manuscript. ***Relates to the time from indication of hypoxia until delivery. Details of ethics approval The study protocol was assessed by the regional ethics presentations. The prevalence of preterminal CTG in committee (REK Vest, 129.08) and defined as a project of breech presentations (3%; 95% CI = 1.8–5.1) did not differ quality improvement which, according to Norwegian law significantly from those reported for fetuses of mothers on medical research, does not require written patient con- with diabetes mellitus (8.6%; 95% CI = 4.0–17.5) or gesta- sent for their involvement. tional diabetes (1.0%; 95% CI = 0.3–2.8).41 The progres- sion of CTG abnormalities to a preterminal pattern Funding without concomitant ST changes has been found in preg- JK was supported by the Western Norway Regional Health 41 nancies complicated by diabetes mellitus, intrapartum Authority. sepsis,42 and in breech presentation (in the present study). This deserves further investigation. Acknowledgements 43,44 In line with previous research, we found that breech We thank Berit Aldahl, Ingrid Borthen, Eirin Butt, Thomas presentation was associated with acidaemia, hypercapnia Hahn, Ferenc Macsali, Grete Midbøe and Elisabeth Wik for and hypoxaemia, with the differences being more promi- their support in data collection. & nent in the umbilical artery than in the vein. Another study – found that cord acid base levels at delivery did not vary References with the type of fetal presentation.45 Although respiratory acidosis is usually well tolerated by 1 Hannah ME, Hannah WJ, Hewson SA, Hodnett ED, Saigal S, Willan the fetus, cord metabolic acidosis is associated with signifi- AR. Planned caesarean section versus planned vaginal birth for 46 breech presentation at term: a randomised multicentre trial. Term cant neonatal short-term morbidity. Thus, it is reassuring – > Breech Trial Collaborative Group. Lancet 2000;356:1375 83. that the frequency of neonates with BDecf 12 mmol/l was 2 Hartnack Tharin JE, Rasmussen S, Krebs L. Consequences of the Term more than 60% lower in the present study than in the Breech Trial in Denmark. Acta Obstet Gynecol Scand 2011;90:767–71. 1 TBT. Furthermore, the increased frequency of cord acido- 3 Herbst A, Kall€ en A. Term breech delivery in Sweden: mortality sis in breech presentation was not paralleled by an increase relative to fetal presentation and planned mode of delivery. Acta – in NICU transfer or NE. Obstet Gynecol Scand 2005;84:593 601. 4 Rietberg CC, Elferink-Stinkens PM, Visser GH. The effect of the Despite no indication of hypoxia during labour and the Term Breech Trial on medical intervention behaviour and neonatal absence of acidosis at delivery, one neonate died after a outcome in The Netherlands: an analysis of 35,453 term breech vaginal breech delivery. Prenatal brain damage could have infants. BJOG 2005;112:205–9.

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ª 2014 Royal College of Obstetricians and Gynaecologists 7 Kessler et al.

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