Live Births in Women over 40 Years of Age Correlate with Obesity Rates.

Aims: This cross-sectional study aimed to analyze the relationship between live birth and the prevalence of obesity in Chinese women over 40 years of age.

Methods: From April to November 2011, the Endocrinology Branch of the Chinese Medical Association conducted the REACTION project, a national, multicenter, cross-sectional study of Chinese adults aged 40 years and older. Demographic and medical data were collected through validated questionnaires and equipment. Anthropometric indicators, blood pressure, and biochemical data were measured by professional medical personnel. Data were analyzed using descriptive statistics and logistic analysis. Multivariate regression models were used to analyze obesity-related risk factors.

Results: The prevalence of obesity among women increased gradually from 3.8% to 6.0% with an increasing number of live births. Women with two live births had the highest prevalence of overweight at 34.3%. Overall, the obesity and overweight rates were slightly higher in premenopausal women than in postmenopausal women. Univariate regression analysis showed that the risk of obesity in women increased with an increasing number of live births. In addition, multivariate regression analysis showed that the risk of obesity increased with an increasing number of live births in women with systolic blood pressure (SBP) < 121 mmHg or current smoking (P < 0.05).

Conclusion: The risk of obesity increases with the number of live births in Chinese women over 40 years of age with SBP < 121 mmHg or current smoking. Our findings may facilitate the development of interventions to prevent obesity in this population.