Abstract
INTRODUCTION AND HYPOTHESIS: The objective was to investigate how weight change across and after the childbearing years was associated with urinary incontinence (UI) in midlife. METHODS: Data were obtained from 35,645 women responding to the Maternal Follow-up questionnaire in the Danish National Birth Cohort in 2013-2014. Outcome was self-reported UI and its subtypes. Exposures were changes in body mass index (BMI) across and after the childbearing years. Adjusted odds ratios were estimated using logistic regression. RESULTS: At follow-up, the mean age was 44 years and 32% experienced UI. Compared with stable weight, weight gain across the childbearing years of > 1 to 3, > 3 to 5 or > 5 BMI units increased the odds of any UI by 15%, 27%, and 41% respectively. For mixed UI, the odds increased by 23%, 41%, and 68% in these groups. Weight gain after childbearing showed the same pattern, but with a higher increase in the odds of mixed UI (25%, 60%, and 95% in the respective groups). Women with any weight loss during this period had 9% lower odds of any UI than women with a stable weight. CONCLUSIONS: Weight gain across and after childbearing increased the risk of UI in midlife, especially the subtype mixed UI. Weight loss after childbearing decreased the risk.