Is fetal growth discordancy a risk factor for perinatal and neonatal outcomes in twin gestations?

Kim, Keum Jae; Kim, Mi Kyung; Yoo, Hye Kyung; Oh, Hye Eun; Won, Hye Sung; Lee, Pil Ryang; Lee, In Sik; Kim, Ahm; Nam, Joo Hyun

Abstract

OBJECTIVE
To evaluate whether twin discordancy is a risk factor for adverse perinatal and neonatal outcomes.
METHODS
Three hundred and seventy-five twin gestations over 28 weeks of gestation were included in this retrospective study. Medical records of mothers and infants were reviewed. Pregnancies were divided into 2 groups according to the birth weight discordancy(%) between twin neonates(group I;less than 25%, group II;25% or more). Birth weight discordancy was calculated from following formula; (birth weight of larger twin-birth weight of smaller twin)/birth weight of larger twin x 100. Perinatal and neonatal outcomes in group I and II were compared with each other. Also, difference in the outcomes between the smaller and larger twins of group II was evaluated. To evaluate whether birth weight discordancy is an independent variable in predicting poor perinatal and neonatal outcomes, multiple logistic regression analysis was used.
RESULTS
Thirty-seven gestations(9.9%) were documented to belong to group II. Group II showed significantly higher incidence of preeclampsia, placenta previa, and small for gestational age infants(p<0.01, p<0.05 and p<0.001, respectively). The group also showed higher incidence of adverse neonatal outcomes(admission to neonatal intensive care unit, respiratory distress syndrome, pneumonia, bronchopulmonary dysplasia, patent ductus arteriosus, intraventricular hemorrhage, retinopathy of prematurity, necrotizing enterocolitis, sepsis, congenital anomaly, neonatal death, p<0.01). Outcomes of the larger and smaller twins of group II were not significantly different with each other except small for gestational age infants(p<0.005). However, birth weight discordancy was not an independent variable in predicting adverse perinatal and neonatal outcomes.
CONCLUSION
Fetal growth discordancy of 25% or more should be regarded as a risk factor for adverse perinatal and neonatal outcomes in twin gestations. However it is not an independent factor in predicting adverse perinatal and neonatal outcomes.