(795) Association of body mass index with adverse pregnancy outcomes when stratified by cardiovascular health

Friday, January 31, 2025

10:30 AM – 12:30 PM

Submitting Author and Presenting Author(s)

Karen J. Gibbins, MD, MSCI (she/her/hers)

Associate Professor
Oregon Health & Science University
Portland, Oregon, United States

Coauthor(s)

NM

Nicole E. Marshall, MD

Associate Professor
Oregon Health & Science University
Portland, Oregon, United States
Amy M. Valent, DO, MCR (she/her/hers)

Associate Professor, Dept. of OBGYN - MFM Division
Oregon Health & Science University
Portland, Oregon, United States

Objective: High body mass index (BMI) is associated with adverse pregnancy outcomes, but it is not a direct measure of cardiovascular health (CVH) and misclassifies many. We aimed to evaluate the association between BMI≥30 and adverse pregnancy outcomes stratified by CVH.

Study Design: Secondary analysis of nuMoM2b multicenter cohort of nulliparas, excluding pregestational diabetes and chronic hypertension. We used American Heart Association’s Life’s Simple 7 to assess CVH. Metrics included smoking, physical activity, healthy diet pattern, total cholesterol, and blood pressure. We omitted BMI given our objective, and we added triglycerides as these are a marker of CVH in pregnancy. We assigned 0 points for Poor category, 1 for Intermediate, and 2 for Ideal for each metric, with maximum total score of 14. Total score was categorized as Poor (1-7), Intermediate (8-11), or Ideal (12-14). Outcomes included adverse perinatal outcomes previously linked to BMI (Table 1). Association between exposures and outcomes were calculated via logistic regression.

Results: 2462 participants were included. 473 had BMI≥30, 134 (5.4%) had Poor CVH, 1740 (70.7%) had Intermediate CVH, and 517 (21.0%) had Ideal CVH. Overall, BMI≥30 was associated with increased HDP (38.7 vs 19.6%, OR 2.6, 95% CI 2.1-3.2), severe preeclampsia (8.3 vs 3.1%, OR 2.8, 95% CI 1.9-4.3), LGA (10.6 vs 4.3%, OR 2.6, 95% CI 1.8-3.8), GDM (7.4% vs 2.6%, OR 3.0, 95% CI 1.9-4.6), and CB (37.0 vs 22.4%, OR 2.0, 95% CI 1.6-2.5). However, when stratified by CVH category, these associations were altered. In the Ideal CVH category, BMI≥30 was only associated with LGA and GDM (Table 1). For some outcomes, like HDP, OR was higher in those with poor CVH and low BMI than those with Ideal CVH and high BMI (Figure 1).

Conclusion: Relying on BMI alone to assess pregnancy risk appears to overestimate risk of BMI≥30 in those with otherwise Ideal CVH and underestimate in those with BMI 18.5-29.9 but Poor CVH. More comprehensive assessment of CVH could result in more accurate risk stratification.