Sonographic atypical vascular coiling of the umbilical cord.

Objective: To investigate whether an atypical umbilical coiling pattern at prenatal sonography is associated with adverse pregnancy outcome.

Methods: A targeted sonographic evaluation of the umbilical cord (UC) was performed in 758 women with singleton gestation, and gestational age above 20 weeks. Atypical coiling was defined as the presence of a spring-shape UC (supercoiling) or an unusual, aperiodic coiling pattern (uncoordinated coiling). Umbilical artery Doppler assessment was conducted in cases with atypical coiling. Pregnancy and neonatal outcomes were investigated.

Results: Of the study population, 7 and 16 fetuses had an umbilical cord with uncoordinated coiling and supercoiling respectively. Three umbilical cords had a single umbilical artery. Eight patients delivered before 34 weeks of gestation. Eight fetuses were growth restricted. In seven cases, abnormal sonographic findings were detected (three meconium peritonitis, two severe hydronephrosis and two cardiac anomalies). One fetus affected by trisomy 18 presented multiple anomalies. Perinatal death occurred in three cases. Of the surviving newborns, eight were admitted to NICU. Umbilical artery Doppler waveforms presented a systolic notch in seven (30.4%) cases.

Conclusions: The presence of an atypical umbilical cord vascular coiling is associated with an increased risk of unfavourable pregnancy outcome. The identification of an umbilical artery notch at Doppler investigation is frequently associated with an atypical UC coiling pattern.