No Adverse Outcomes in Efforts to Reposition Breech Baby

Efforts to reposition a fetus in the breech position at term with external cephalic version (ECV) do not compromise perinatal outcomes compared with expectant management and significantly improve the likelihood of a vaginal delivery, according to new research.



"An ECV attempt at term is not associated with increased perinatal morbidity or mortality compared with expectant management," say the authors.

"Moreover, although success can be difficult to predict reliably, an ECV attempt does result in a significantly reduced chance of cesarean delivery when compared with expectant management," they add.

Indeed, although only 40% of ECV attempts were successful, among those that were, 79% of women went on to give birth vaginally.


For the retrospective study, researchers evaluated data on 4117 women who presented at the Northwestern Memorial Hospital between 2006 and 2016 with singleton pregnancies in breech positions at 37 weeks' gestation or greater.

The study was published in the August issue of Obstetrics & Gynecology and led by Moeun Son, MD, Division of Maternal-Fetal Medicine and Department of Obstetrics and Gynecology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, and colleagues.

Only a Third of Patients Attempted ECV

Of the women, ECV was attempted in only about a third of patients (n = 1263; 30.7%), and 509 (40.3%) of the attempts resulted in successful repositioning of the fetus.

For the primary outcome — a composite of perinatal morbidity and mortality — there were no significant differences between those who did and did not receive an attempted ECV (2.9% vs 2.5%; P = .46).

The full composite of the primary outcome included stillbirth, neonatal death within 72 hours, Apgar score less than 5 at 5 minutes, umbilical artery pH less than 7.0, base deficit 12 mmol/L or greater, or neonatal therapeutic hypothermia.

There were also no significant differences between those who did and did not receive attempted ECV in terms of secondary outcomes including neonatal intensive care unit admission (3.6% vs 3.3%; P = .53) and neonatal anemia (1.6% vs 1.2%; P = .36).

The results remained consistent after adjustment for potential confounders (adjusted odds ratio, 1.02).

Among women who underwent attempted ECV, more were non-Hispanic white, multiparous, and had a lower mean body mass index at time of delivery compared with those who did not have an ECV attempt.

Almost 80% of Those With Successful ECV Had Vaginal Birth

Importantly, among the 40% of women who had successful ECV, as many as 79% delivered vaginally, whereas among those who did not undergo an ECV attempt and continued to have nonvertex fetal presentation at time of delivery, fewer than 1% delivered vaginally.

"Although success can be difficult to predict reliably, an ECV attempt does result in a significantly reduced chance of cesarean delivery when compared with expectant management," stress Son and colleagues.

"As such, these data support the existing recommendations that an ECV attempt should be encouraged when fetal malpresentation exists at term."

Exclusionary factors in the study included having a history of a prior cesarean delivery or a known placenta previa or cavity-entering myomectomy.

Study limitations include the fact that the 40% success rate of ECV attempts is low compared with previous reports, and with only 31% of women undergoing an ECV attempt, the results may not be generalizability to other sites, the authors note.

And the study could have some selection bias in that the women who ultimately did undergo an ECV attempt likely were thought to be better candidates for the procedure.

The authors add, however, that although the findings are consistent with previous research, the composite outcome provides improved and more detailed clinical significance compared with previous studies, and the comparison of post-ECV attempt outcomes is with the appropriate comparison group of women who also had breech presentation but did not undergo an ECV attempt.

ECV Recommended by ACOG but Uptake Is Low

Breech fetal positioning occurs in approximately 3% to 4% of term pregnancies, and ECV attempts in such cases are recommended by the American College of Obstetricians and Gynecologists (ACOG) in eligible women without contraindications, amid evidence that the efforts reduce the need for cesarean deliveries.

As previously reported by Medscape Medical News, ACOG's recommendations for ECV, published in 2016, describe evidence supporting the recommendation to be "good and consistent" and state that "all women who are near term with breech presentations should be offered an ECV attempt if there are no contraindications."

But despite this evidence, about 20% to 40% of women with breech presentations who are eligible are not offered ECV or choose not to undergo it, according to one study (J Obstet Gynaecol. 2002;22:486-488).

And in a more recent study out of the Netherlands, researchers report the leading barriers for ECV (Midwifery. 2014;30:324-330).

Among patients, these barriers were fear, preference for a planned cesarean delivery, or incomplete information. Among healthcare professionals, the main barriers were a lack of knowledge necessary to fully educate and counsel patients on ECV, and the inability to counsel women who preferred a primary cesarean delivery.

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