The Relationship between Gestational Weight Gain and Cesarean Delivery among Patients undergoing Induction of Labor.

OBJECTIVE

This study aimed to determine the impact of pregnancy weight gain above National Academy of Medicine (NAM) guidelines on cesarean delivery rates following induction.

STUDY DESIGN

This is a secondary analysis of a prospective cohort study of patients who underwent induction at a single tertiary care center between July 2017 and July 2019. Included in the primary study were patients undergoing term (≥37 weeks) labor induction with a singleton gestation, intact membranes, and unfavorable cervical examination (Bishop score of ≤6 and cervical dilation ≤ 2 cm). Eligibility for this analysis was limited to patients with a documented prenatal body mass index (BMI) < 20 weeks' gestation. The primary exposure was gestational weight gain greater than NAM guidelines (WGGG) for a patient's initial BMI category. The primary outcome was cesarean delivery for any indication.

RESULTS

Of 1,610 patients included in the original cohort, 1,174 (72.9%) met inclusion criteria for this analysis and 517 (44.0%) of these had weight gain above NAM guidelines. Of the entire cohort, 60.0% were Black and 52.7% had private insurance. In total, 160 patients (31%) with WGGG underwent cesarean compared with 127 patients (19.3%) without WGGG ( < 0.001), which equates to a 59% increased odds of cesarean when controlling for initial BMI category, parity, gestational diabetes, and indication for induction (Adjusted Odds Ratio [aOR] 1.58, 95% confidence interval [CI] 1.17-2.12). Among only nulliparous patients, WGGG was associated with an increased odds of cesarean (26.4 vs. 38.2%, aOR 1.50, 95% CI 1.07-2.10). In multiparous patients, however, there was no difference in cesarean between those with and without WGGG (8.8 vs. 14.1%, aOR 1.85, 95% CI 0.96-3.58).

CONCLUSION

This study demonstrates that weight gain above NAM guidelines is associated with more than a 50% increased odds of cesarean. Patients should be informed of this association as gestational weight gain may be a modifiable risk factor for cesarean delivery.

KEY POINTS

· Weight gain above NAM guidelines was associated with a 59% increased odds of cesarean delivery.. · Nulliparous patients with weight gain above NAM guidelines are at higher risk of cesarean delivery.. · No difference in cesarean delivery among multiparous patients regardless of gestational weight gain..