Assessment of Risk Factors and Outcomes of Twin Pregnancies with Weight Discordance

Document Type : Original Article


1 Assistant Professor of Obstetrics & Gynecology, Faculty of Medicine, Gillan University of Medical Sciences, Gillan, Iran

2 Associate Professor of Microbiology, Faculty of Medicine, Gillan University of Medical Sciences, Gillan, Iran


Introduction: Unusual increase of multifetal pregnancy is a public health problem. The prevalence of complications during pregnancy, maternal mortality, preterm labor, and fetal and neonatal complications in twin pregnancy is more than single pregnancy. Fetuses’ weight discordance is one of the important complications that may increase the unpleasant consequences of twin pregnancies such as the risk of fetal and neonatal mortality and disability.
Methods and Material: In this analytical study all the archived files (667) of twin pregnancies delivered during 1997-2005 in Alzahra and Rasoul Akram hospitals in Rasht city (north of Iran) were studied. Birth weight differences of the twins were stratified into the following groups: discordant twins (birth weight differences ≥20%) and concordant twins (birth weight differences<20%). Then the frequency of risk factors such as maternal age, parity, pre-eclampsia, and the outcomes such as preterm labor, non-cephalic- cephalic presentation, and cesarean delivery were compared in these groups. The data were analyzed by using the SPSS software version 12. X² and t tests were used to compare between groups.
Results: Of thetotal 667 twin deliveries, 78.4% were concordant and 21.6% were discordant. There was significant correlation between discordance and preterm labor and non cephalic- cephalic presentation (p<0.05). But there was not significant correlation between discordance and maternal age, parity, preeclampsia, and cesarean delivery.
Conclusion: Twin pregnancy with weight discordance is a very high risk pregnancy, which can be accompanied by non cephalic- cephalic presentation and preterm labor. It needs particular attention for detection and monitoring. Regular prenatal visits should be arranged in these pregnancies.


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