The Impact of Body Mass Index on Postpartum Infectious Morbidities and Wound Complications: A Study of Extremes

Abstract

Background As body mass index increases, the risk of postpartum infections has been shown to increase. However, most studies lump women with a body mass index (BMI) of above 40kg/m2 together, making risk assessment for women in higher BMI categories challenging. The objective of this study was to evaluate the impact of extreme obesity on postpartum infectious morbidity and wound complications during the postpartum period. Study Design The present study is a secondary analysis of women who underwent cesarean delivery and had BMI > 40 kg/m2 in the Maternal Fetal Medicine Units Cesarean Registry. The primary outcome was a composite of postpartum infectious morbidity including endometritis, wound infection, inpatient wound complication prior to discharge, and readmission due to wound complications. Appropriate statistics used to compare baseline demographics, pregnancy complications, and primary outcomes among women by increasing BMI groups (40-49.9kg/m2, 50-59.9kg/m2, 60-69.9kg/m2, and >70kg/m2). Results Rates of postpartum infectious morbidity increased with BMI category (11.7% body mass index 50-59.9 kg/m2; 13.7% BMI 60-69.9 kg/m2, 21.9%; and BMI >70+ kg/m2; p=0.001). Readmission for wound complications also increased with BMI (3.1% for BMI 50-59.9 kg/m2; 6.2% for BMI 60-69.9 kg/m2; and 9.4% for BMI >70+kg/m2; p=0.001). After adjusting for confounders, increased BMI 70+ kg/m2 category remained the most significant predictor of postpartum infectious complications compared to women with BMI 40-49.9 kg/m2 (aOR 6.38; 95% CI 1.37-29.7). The adjusted odds of readmission also increased with BMI (aOR 2.33 (95%CI 1.35-4.02) BMI 50-59.9kg/m2, aOR 4.91 (95% CI 2.07-11.7) BMI 60-69.9kg/m2, aOR 36.2 (7.45-176) for BMI >70kg/m2). Conclusion Women with BMI 50-70+kg/m2 are at an increased risk of postpartum wound infections and complications compared to women with BMI 40-49.9kg/m2. These data provide increased guidance for counseling women with an extremely elevated body mass index and highlight the importance of postpartum wound prevention bundles.

Early Postpartum Hospital Encounters among Patients with Genitourinary and Wound Infections during Hospitalization for Birth

“…18 Confounders were also identified a priori based on prior knowledge, causal diagrams, and available data. [2][3][4]10,[14][15][16][18][19][20]23 They included social factors (educational attainment, expected method of payment for delivery, race-ethnicity), parity, and comorbidities at delivery, using a weighted obstetric comorbidity index of medical and obstetric comorbidities, 24,25 advanced age, high BMI, and history of cesarean birth. We also identified mode of birth (vaginal or cesarean) a priori as an effect modifier and stratified analyses by mode of birth.…”