Gestational Weight Gain In Twin Pregnancies And Its Association With Maternal And Neonatal Outcomes

Objective To investigate the optimal gestational weight gain(GWG)in twin pregnancies and assess the impact of GWG on pregnancy outcomes.Methods A retrospective cohort of twin pregnancies(1330 cases)was conducted at International Peace Maternity and Child Health Hospital,Shanghai China from January 1,2012 to the June 30,2015.Optimal GWG was calculated based on the study subjects(1137 cases)who delivered normal twins and without other system diseases.Then we chose the women who delivered their twins at 37-38 weeks of gestation to evaluate the association between the abnormal GWG and birth weight as well as maternal complications.Results The optimal GWG of overall women with twin conception was about15-21 kg.According to the pre-pregnancy BMI,the optimal GWG was15.1-22.1 kg for women with BMI<18.5 kg/m~2,14.8-21.1 kg for BMI between 18.5 and 23.9 kg/m~2,and 13.5-21.9 kg for BMI≥25 kg/m~2,respectively(P=0.886).Comparing poor,normal,and excessive weight gain,the mean birth weight of the twins increased significantly from2626.1±225.8g、2680.1±237.9g、2751.9±257.1g(P=0.000).However,gestational diabetes was associated with a decreased risk of high GWG(P=0.000),and the proportion of women with gestational hypertension(P=0.213)or pre-eclampsia(P=0.223)did not increase significantly across the three subgroups.Conclusion Women with twin conception should gain weight about 15-21 kg during pregnancy.Excessive weight gain in term twin gestations,as defined by this recommendation presented in our study,does not appear to be associated with worse maternal outcomes and is associated with a larger birth weight.