Pregnancy after bariatric surgery: persistent obesity and longer time to conception influences peripartum outcomes more than the type of operation.

BACKGROUND

While women may seek metabolic and bariatric surgery (MBS) to achieve pregnancy, conflicting data exist on how MBS affects pregnancy and fetal outcomes. Additionally, despite existing consensus recommendations for micronutrient monitoring, adherence to recommended screening is unknown.

OBJECTIVES

Evaluate post-MBS pregnancy outcomes and clinical adherence to micronutrient monitoring recommendations.

SETTING

University Hospital, United States.

METHODS

A retrospective cohort study of singleton, live-birth pregnancies in post-MBS patients from 2008 to 2023 was performed. Mother and neonate weight, pregnancy comorbidities, peripartum outcomes, and micronutrient results were analyzed using descriptive statistics and Chi-square tests.

RESULTS

In 139 patients (99 Roux-en-Y gastric bypass (RYGB)/duodenal switch (DS) and 40 sleeve gastrectomy (SG)/adjustable gastric band (AGB)), we evaluated 169 singleton, live birth pregnancies. Mean body mass index (BMI) at MBS and preconception were 46.5 ± 8.7 and 34.0 ± 7.7 kg/m2, respectively. Median time to conception (TTC) was 37.6 months (IQR 50.2). Vaginal deliveries were common (62.1%), but emergency cesarean section was required in 9.5% of pregnancies. SG/AGB compared to RYGB/DS, longer TTC, and preconception obesity were associated with peripartum hypertension (odds ratio [OR] 2.65, 95% confidence interval [CI] 1.19-5.91; OR 6.90, 95% CI 1.55-30.80; OR 2.67, 95% CI 1.16-6.11, respectively). Longer TTC and preconception obesity were also associated with diabetes (OR 2.20, 95% CI 1.0009-4.83; OR 2.57, 95% CI 1.2-5.46, respectively). While prenatal supplementation was common (86.4%), micronutrient monitoring (any vitamin B, 71.6%; any micronutrient, 74.0%; iron, 52%) was subpar.

CONCLUSIONS

We found that longer TTC and persistent obesity increased patient risk for peripartum complications. Support to help patients achieve lower preconception weight may reduce peripartum complications.