A Meta-Analysis About The Effects Of Different Gestational Timing On Maternal And Fetal Outcomes After Bariatric Surgery

Purpose:Obesity is a common endocrine disease,more and more people choose bariatric surgery for treatment;On the one hand,bariatric surgery can reduce the incidence of pregnancy complications in obese patients,but premature pregnancy may bring certain risks to pregnant women and fetus due to the operation and the change of postoperative nutritional status.Attacked on reducing postoperative different timing of pregnancy on maternal and fetal outcomes research on the effects of the existence of has not yet had a unified conclusion.Therefore,we conducted the Meta-analysis,in order to use the update research from the angle of the maternal and infant outcomes know the appropriate time to the bariatric surgery after pregnancy,so as to provide reference for clinical practice.Methods:A comprehensive search was conducted on Pub Med,Cochrane Library,Embase,and Science Direct,and the literature on the selection of pregnancy time after bariatric surgery published before July 9,2020 was conducted.Two researchers independently screened the literature according to the inclusion criteria and exclusion criteria,and the included studies were case-control studies and retrospective cohort studies.Newcastle-Ottawa scale score was used to evaluate the quality of the included literatures,and Rev Man 5.3 software was used for statistical analysis.According to the results of heterogeneity test,the pooled effect size was calculated using a random effect model（P≤0.1 or I²>50%）or a fixed effect model（P>0.1 and I²≤50%）.The statistical results of the Meta-analysis were represented by forest plots,and the combined effect size was Odds Ratio（OR）.The primary outcome measures were sample sizes of gestational diabetes mellitus（GDM）,gestational hypertension,preterm delivery,cesarean section,large for gestational age（LGA）,small for gestational age（SGA）,and Admission to the Neonatal Intensive Care Unit（NICU）Results:The results showed that there were no significant differences in the risk of gestational diabetes mellitus,gestational hypertension,preterm delivery,cesarean section,large for gestational age,small for gestational age,and neonatal NICU admission among the pregnancy groups of 12,18 or 24 months after bariatric surgery（P>0.05）.Conclusions:There was no significant difference in the risk of maternal and infant outcomes（gestational diabetes mellitus,gestational hypertension,preterm delivery,cesarean section,older than gestational age,younger than gestational age,and neonatal NICU admission）at different gestational timing after bariatric surgery in the population grouped by time points.Therefore,based on the earliest postoperative gestation time point included in the study,our results suggest that pregnancy or contraception within 12 months after bariatric surgery has no significant effect on maternal and infant outcomes.However,there is a case report of a pregnant patient with GDM at 4 months after bariatric surgery.Due to fetal distress at 35⁺²weeks of gestation,a premature baby was delivered by cesarean section,suggesting that pregnancy in the short term after bariatric surgery may be the cause of the adverse outcomes of mother and child.Therefore,pregnancy in the short term after bariatric surgery may be at risk.Due to insufficient data included in the study,the maternal and infant outcomes assessed in this study were limited,lacking important evaluations such as postpartum hemorrhage and perinatal death of child,and the results still need to be carefully interpreted.Moreover,the sample size of the included studies is very small,and more high-quality and large sample studies are needed for verification.