Endocrine Abstracts

JOINT3587

Introduction: 50-80% of individuals undergoing bariatric surgery (BS) are women of reproductive age. Pregnancies following BS are associated with a higher risk of intrauterine growth restriction (IUGR) and low birth weight (LBW), but lower incidence of macrosomia, preeclampsia, and gestational diabetes (GD).

Methods: Our observational, retrospective study compared maternal-fetal outcomes of women who became pregnant after BS with matched controls based on age and BMI, using data from deliveries at our center between June 2019 and September 2024.

Results: Each group included 51 women, with an average BMI of 30.3 kg/m² and an average age of 36 years. Gastric sleeve (68.6%) was the most common procedure in the BS group and resulted in an average 33% weight loss pre-pregnancy. Despite a high rate of nutritional deficiencies (52.9% folic acid, 41.2% iron and 9.8% vitamin B12) and anemia (21.6%), there were no differences in weight gain during pregnancy (12% vs. 14% post-BS, P = 0.535), with an average weight gain of 10 kg in both groups. The mean gestational age was also similar between groups (272 days vs. 273 days post-BS, P = 0.779), as was the prevalence of preterm births, dystocia, and cesarean sections. There were no significant differences in pre-pregnancy diagnoses of diabetes or hypertension, nor in the need for medically assisted reproduction. Maternal outcomes also showed less frequent need of pharmacological treatment for GD in the post-BS group (RR 0.337, CI 0.13–0.87), while gestational hypertension, preeclampsia, and macrosomia were more prevalent in controls in a not statistically significant way. Neonatal outcomes indicated similar rates of LBW and malformations between groups. However, post-BS newborns had lower birth weights (3051g vs. 3231g, P = 0.162) and higher IUGR risk (RR 2.11, CI 1.71–2.60).

Conclusion: Post-BS pregnancies showed reduced prevalences of hypertensive disorders, macrosomia and need for GD treatment but increased risks of IUGR, emphasizing the need for specialized prenatal care.