Obesity and postpartum hospital use among individuals without additional medical comorbidities

OBJECTIVE: The objective of this study was to examine whether obesity without preexisting or gestational comorbidities is associated with postpartum hospital use (PHU). METHODS: We studied 2016 to 2018 birth certificate and discharge data on 178,729 New York City births without International Classification of Diseases, Tenth Revision (ICD-10) codes at delivery for diabetes; hypertension; placental disease; anemia; thyrotoxicosis; bariatric surgery; and pulmonary, cardiac, renal, bleeding, autoimmune, digestive, neuromuscular, mental, or substance-use disorders. We defined PHU as ≥1 readmission or emergency department visit within 30 days of delivery discharge. We used ICD-10 codes to specify postpartum hypertension, infection, or hemorrhage during PHU (i.e., "cause-specific PHU") because these are leading mortality causes. We examined associations between prepregnancy BMI and PHU using multivariable logistic regression. RESULTS: PHU incidence was 3.7% for those with normal weight, 5.1% for those with overweight, 6.3% for those with class 1 or 2 obesity, and 9.1% for those with class 3 obesity. A positive association persisted after adjustment. Obesity was associated with cause-specific PHU of postpartum hypertension (adjusted odds ratio [aOR]: 2.2, 95% confidence limits [CL]: 1.8-2.7, normal weight referent) and wound infection (aOR: 1.5, 95% CL: 1.2-1.8), but not hemorrhage (aOR: 0.9, 95% CL: 0.7-1.3), mastitis, or genitourinary infection (aOR: 1.1, 95% CL: 0.9-1.3). CONCLUSIONS: Among individuals without other comorbidities, elevated BMI was associated with PHU. Findings can inform obstetric management to reduce morbidity during the critical fourth trimester.