(492) The association between the sum of fetal weights in twin pregnancies and perinatal complications

Over distended uterus, due to polyhydramnios or large for gestational-age fetus, is known to be associated with perinatal complications such as placental abruption and post-partum hemorrhage. We aimed to study perinatal complications of twin pregnancies associated with the sum of birthweights (BW).

Study Design: This was a population-based analysis of all twin birth occurring between the years 1991-2021, in a large tertiary medical center. The sum of birthweights was calculated, and the mean sum was compared between pregnancies with and without the following complications:  placental abruption, non-reassuring fetal heart rate, 5 minutes Apgar score < 7, uterine rupture, perinatal death, post-partum hemorrhage, and blood transfusion. Multivariable logistic models were used to study the association between increased sum of birthweights and the adverse perinatal outcomes, while adjusting for mode of conception and maternal age.   

Results:

During the study period, 6626 twin deliveries occurred. The following complications were associated with lower BW sum: non-reassuring fetal heart rate, placental abruption, cesarean delivery, low 5 minutes Apgar score and perinatal death (Table). Higher mean of BW sum was associated with higher risk for post-partum hemorrhage (5029gr. ± 1109 vs. 4491gr. ± 1118, p< 0.001), although no association was found with the need for blood transfusion. The risk of uterine rupture was not associated with higher BW sum. The results were similar in the multivariable analyses) Figure).

Conclusion:

Over distended uterus of twin pregnancy is not associated with higher risk for perinatal complications, besides post-partum hemorrhage.