Perinatal outcomes in twin pregnancies with discordant Doppler velocimetric findings

The purpose of this study was to investigate whether poor perinatal outcomes are more common in twins with abnormal umbilical artery Doppler velocimetric findings than in their siblings with normal findings.

A matched-pair cohort analysis of twin pregnancies with discordant umbilical artery Doppler velocimetric findings (one normal and one abnormal) was performed. Both severely abnormal findings (defined as absent or reversed flow in one twin; n = 23) and mildly abnormal findings (defined as an elevated systolic to diastolic ratio in one twin; n = 28) were included. The matched twins provided a gestational age-and demographically matched comparison group. Outcomes measured included intrauterine fetal death, oligohydramnios, intrauterine growth restriction, and neonatal outcomes (birth weight, Apgar scores, intraventricular hemorrhage, necrotizing enterocolitis, respiratory distress syndrome, bronchopulmonary dysplasia, and sepsis). Associations between abnormal Doppler velocimetric findings and perinatal outcomes were estimated using matched logistic regression analysis.

Among this cohort of twin pregnancies with discordant umbilical artery Doppler velocimetric findings, oligohydramnios and intrauterine growth restriction were more frequent in twin fetuses with abnormal findings. Adverse neonatal outcomes were high in both groups (57% among those with normal findings and 49% among those with abnormal findings) because of the overwhelming contribution of preterm delivery (mean gestational age at delivery, 33.3 weeks) but were not significantly different between those fetuses with abnormal findings compared to their cotwins with normal findings.

Our results do not show an association between abnormal umbilical artery Doppler velocimetric findings and short-term adverse neonatal outcomes.