Effect of Gestational Weight Gain on Length of Induction of Labor [ID: 1377561

Abstract

INTRODUCTION: Review of institutional data found an association between maternal obesity and increased cesarean delivery (CD) among nulliparous, term, single, vertex (NTSV) pregnancies. To identify modifiable risk factors for CD, we evaluated the relationship of gestational weight gain (GWG) to length of induction of labor. METHODS: From January 2020 to May 2021, NTSV inductions were identified via retrospective chart review (IRB#4954). Gestational weight gain according to prepregnancy body mass index (BMI) was categorized using ACOG standards as appropriate, insufficient, or excessive. Time of initial induction agent to delivery time equated to total induction time. Chi square, t test, and regression analyses were performed where appropriate. RESULTS: Of 1,031 inductions, 244 (24%) patients had appropriate, 160 (15%) had insufficient, and 627 (61%) had excessive GWG. 366 (36%) had prepregnancy BMI greater than 30. Average total induction times for appropriate, insufficient, and excessive GWG were 1,179, 1,072, and 1,286 minutes, respectively. Excessive GWG was a positive predictor of length of induction (P<.001). Additionally, those with excessive GWG labored significantly longer with ruptured membranes (84 minutes) than those with appropriate GWG (P=.006). CONCLUSION: Excessive GWG correlated with 107 additional minutes in the induction process and more time with ruptured membranes. These data emphasize the importance of appropriate GWG particularly in patients beginning pregnancy with obesity. Patients with obesity otherwise have worse pregnancy outcomes; therefore, nutrition and exercise counseling during prenatal care could be advantageous. These data also help inform counseling and preparation on labor units, particularly as inductions become more prevalent.