Effect Of First Caesarean Delivery On Subsequent Pregnancy

Objective1.To explore the association between a previous caesarean delivery and perinatal outcomes in a subsequent pregnancy.2.To compare the perinatal outcomes of a subsequent pregnancy in women who underwent an indicated or non-indicated caesarean section(CS)in their first delivery.3.To evaluate the association between short interpregnancy interval(delivery to conception)and adverse pregnancy outcomes in women with first CS.Methods1.This retrospective cohort study included women who underwent singleton deliveries at the International Peace Maternity and Child Health Hospital from January 2013 to December 2016.There were two groups(spontaneous vaginal delivery(SVD)group and CS group)according to the first mode of delivery in the cohort.The association between CS in the first delivery and adverse perinatal outcomes in the next birth was assessed.2.A prospective cohort study was conducted to recruit subjects who had a previous CS at the International Peace Maternity and Child Health Hospital and Women Hospital School of Medicine Zhejiang University between 2012 and 2015,when they underwent prenatal care in the two hospitals from January 2014 to October 2016.1)The women were divided into previous indicated CS group and non-indicated CS group according to the indications of the first CS.Multivariate logistic regression was conducted to evaluated the risk of adverse perinatal outcomes in the subsequent pregnancy in the two groups.2)Interpregnancy interval(IPI)was modeled as a categorical variable classified as:0-12 months,12-18 months,18-24 months(reference category),24-30 months,30-36 months,and 36 months or greater.Risks of perinatal outcomes for each IPI were estimated.Results1.CS delivery in the subsequent pregnancy was more likely for women who underwent CS in their first birth than for women with previous SVD.CS in the first birth was also associated with a significantly increased risk of adverse outcomes in the subsequent pregnancy,especially in women who underwent a non-indicated CS.Adverse perinatal outcomes included pregnancy-induced hypertension(PIH),gestational diabetes mellitus(GDM),gestational anaemia,placenta previa,placenta accreta,and polyhydramnios in mothers and preterm delivery,low birth weight,macrosomia,and neonatal jaundice in babies.2.Compared with first indicated CS group,women with first non-indicated CS were3.46 times more likely to have ICP and 2.13 times more likely to have placenta previa in the next pregnancy.In the subgroup analysis,women with previous non-indicated CS were 1.62 times more likely to experience GDM,3.46 times more likely to have ICP and 2.13 times more likely to suffer placenta previa in the next birth.3.Abnormal placenta,maternal severe complications,small for gestational age(SGA)and neonatal infection risks were increased at 0-12 months compared with 18-24 months IPI for women with first CS.Risks of maternal severe complications and SGA were also increased at 12-18 months than 18-24 months IPI,especially for women aged 31 years or older at the second delivery.4.Risks of gestational anemia for women with first CS were increased with the duration of IPI when IPI was more than 24 months.And the risks of GDM were increased with the extension of IPI for women aged over 30 years.Conclusion1.CS in the first delivery markedly increases the risk of repeated CS and perinatal complications in the subsequent pregnancy,especially in women with a non-indicated CS.2.Women with a first non-indicated CS have higher risks of maternal complications in the next pregnancy than women with a previous indicated CS.3.Short interpregnancy intervals are associated with increased risks for adverse perinatal outcomes for women with previous CS,and relation to maternal age at the second delivey.