[Cord accident after external cephalic version: Reality or mostly myth?]

Prediction model of success for external cephalic version. Complications and perinatal outcomes after a successful version

AIM

External cephalic version (ECV) is an effective and safe technique for avoiding breech presentation at birth. However, it continues rejected by many women. The aim of this study is to develop a predictive model of success of external cephalic version, determine the safety of the technique and perinatal outcomes after successful version.

METHODS

Data from 317 versions performed over a 6-year period were collected. Different clinical and ultrasound variables, complications, vaginal delivery after successful version and perinatal outcomes were analyzed.

RESULTS

The overall success rate was 72% (229 of 317 versions). The variables most related to success were parity, placental location, amniotic fluid volume, fetal sex, fetal head palpation and descent of the presenting part. A model for calculating the probability of success was developed in which to input parity, placentation and amniotic fluid data. The model correctly classified 98.8% of successful technique and 74% of all women. Complications were very few and mostly mild. Of women who had success, 77% (163 of 212) had a vaginal birth. No differences between neonatal outcomes were found.

CONCLUSION

External cephalic version is a successful, safe technique with a high rate of subsequent vaginal delivery. A success prediction model based on some very easily obtained variables can personalize the probability of success.

Current Perspectives of Prenatal Sonographic Diagnosis and Clinical Management Challenges of Nuchal Cord(s)

Umbilical cord accidents preceding labor are uncommon. In contrast, nuchal cords are a very common finding at delivery, with reported incidences of a single nuchal cord of approximately between 20% and 35% of all singleton deliveries at term. Multiple loops occur less frequently, with reported incidence rates inverse to the number of nuchal cords involved. Rare cases of up to 10 loops of nuchal cord have been reported. While true knots of the umbilical cord have been associated with a 4–10-fold increased risk of stillbirth, nuchal cord(s) are most often noted at delivery of non-hypoxic non-acidotic newborns, without any evidence of subsequent adverse neonatal outcome. Prior to ultrasound, nuchal cords were suspected clinically following subtle (spontaneous or evoked) electronic fetal heart rate changes. Prenatal sonographic diagnosis, initially limited to real-time gray-scale ultrasound, currently entails additional sonographic modalities, including color Doppler, power Doppler, and three-dimensional sonography, which have enabled increasingly more accurate prenatal sonographic diagnoses of nuchal cord(s). In contrast to true knots of the umbilical cord (which are often missed at sonography, reflecting the inability to visualize the entire umbilical cord, and hence are often incidental findings at delivery), nuchal cord(s), reflecting their well-defined and sonographically accessible anatomical location (the fetal neck), lend themselves with relative ease to prenatal sonographic diagnosis, with increasingly high sensitivity and specificity rates. While current literature supports that single (and possibly double) nuchal cords are not associated with increased adverse perinatal outcome, emerging literature suggests that cases of ≥3 loops of nuchal cords or in the presence of a coexisting true knot of the umbilicus may be associated with an increased risk of stillbirth or compromised neonatal status at delivery. This commentary will address current perspectives of prenatal sonographic diagnosis and clinical management challenges associated with nuchal cord(s) in singleton pregnancies.