Fetal Vascular Malperfusion Due To Long and Hypercoiled Umbilical Cords Resulting in Recurrent Second Trimester Pregnancy Loss: A Case Series and Literature Review.

BACKGROUND Intrauterine fetal demise due to fetal vascular malperfusion in mid-gestation is a rare occurrence. Abnormally long and hypercoiled umbilical cords are associated with an increased risk of umbilical cord blood flow restriction, which in turn can result in adverse perinatal and maternal outcomes. The factors that regulate umbilical cord development, specifically umbilical cord length and coiling, are poorly understood. METHODS Maternal history, along with fetal and placental findings (post-mortem, pathological, and molecular), were reviewed for a series of 3 consecutive pregnancies that ended in second trimester intrauterine fetal demise. RESULTS All 3 umbilical cords were exceptionally long and hypercoiled, and all placentas showed evidence of high-grade fetal vascular malperfusion. At fetopsy, all 3 fetuses were developmentally normal for gestational age and lacked congenital anomalies. Maternal medical history and antenatal testing (including an extensive work-up for maternal hypercoagulability syndromes) were normal and/or noncontributory. CONCLUSION Although excessively long and hypercoiled cords are generally thought of as sporadic, nongenetic events, rare examples of recurrent intrauterine fetal demise secondary to such exist have been reported. This intrafamilial clustering of a rare event is suggestive that at least a subset of hypercoiled, long umbilical cords may have an underlying genetic etiology.