Super-obesity and risk for early and late pre-eclampsia

BJOG. 2010 Jul;117(8):997-1004. doi: 10.1111/j.1471-0528.2010.02593.x. Epub 2010 May 19.


Objective: To examine the association between obesity subtypes and risk of early and late pre-eclampsia.

Design: Population-based retrospective study.

Setting: State of Missouri maternally linked birth cohort files.

Population: All singleton live births in the state of Missouri from 1989 to 2005.

Methods: The body mass index (BMI) was used to classify women as normal weight (BMI = 18.5-24.9 kg/m(2)), class I obesity (BMI = 30-34.9 kg/m(2)), class II obesity (BMI = 35-39.9 kg/m(2)), class III obesity (BMI = 40-49.9 kg/m(2)) or super-obesity (BMI > or = 50 kg/m(2)). Adjusted odds ratios (OR) and 95% confidence intervals (CI) for the association between obesity and the risk of pre-eclampsia were obtained from logistic regression models with adjustment for intracluster correlation.

Results: The rate of pre-eclampsia increased with increasing BMI, with super-obese women having the highest incidence (13.4%). Compared with normal weight women, obese women (BMI > or = 30 kg/m(2)) had a higher risk for pre-eclampsia (OR = 2.59, 95% CI = 2.87-3.01). This risk remained approximately the same for late-onset pre-eclampsia (pre-eclampsia occurring at 34 weeks or more of gestation) and was slightly reduced for early-onset pre-eclampsia (pre-eclampsia occurring at 34 weeks or less of gestation). Within each BMI category, the risk of pre-eclampsia increased with the rate of weight gain. Compared with normal weight mothers with moderate weight gain, super-obese women with a high rate of weight gain had the greatest risk for pre-eclampsia (OR = 7.52, 95% CI = 2.70-21.0).

Conclusion: BMI and rate of weight gain are synergistic risk factors that amplify the burden of pre-eclampsia among super-obese women.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Body Mass Index
  • Female
  • Humans
  • Obesity / complications*
  • Pre-Eclampsia / etiology*
  • Pregnancy
  • Retrospective Studies
  • Risk Factors
  • Weight Gain