Effect of interpregnancy interval on outcomes of transposal pregnancy: a retrospective study

Background: This study was aimed to explore the effect of interpregnancy interval (IPI) on outcomes of transposal pregnancy. Methods: : A retrospective study was conducted in Maternal and Child Health Hospital of Jiaxing, Zhejiang Province in China. The participants were divided into five groups according to IPI: 0-1 year, 2-3 years, 4-5 years, 6-10 years and ³11 years. Logistic analysis was further carried out to explore the differences in the effects of IPI on pregnancy outcomes. Results: : A total of 4862 women were included in this study. (1) The age, gestational diabetes mellitus (GDM), gestational hypertension, preeclampsia, anemia, oligohydramnios, postpartum hemorrhage, placenta previa and cesarean section delivery rate were gradually increased with the prolong of IPI ( P <0.05). (2) After adjusting for potential confounding factors, compared with women in the IPI of 2-3years group, the risk of gestational hypertension ( OR =3.6, 95% CI 1.27-10.26, P =0.016), preeclampsia ( OR =2.44, 95% CI 1.25-4.73, P =0.009), oligohydramnios ( OR =1.81, 95% CI 1.14-2.89, P =0.012) and premature rupture of membranes (PROM) ( OR =1.39, 95% CI 1.04-1.84, P =0.025) were increased significantly for women in the IPI ≥11 years group. After adjusting for potential confounding factors, the risk of anemia, placenta previa, precipitate labor and cesarean section delivery rate in the 6-10 years group and ³11 years group were increased with the prolong of IPI compared with women in the IPI of 2-3 years group. Conclusions: IPI ≥6 years would increase the risk of adverse pregnancy outcomes in the subsequent pregnancy. Healthcare education and consultation should be conducted for women to maintain an appropriate IPI.