Gestational weight change in a diverse pregnancy cohort and mortality over 50 years: a prospective observational cohort study.

High weight gain in pregnancy is associated with greater postpartum weight retention, yet long-term implications remain unknown. We aimed to assess whether gestational weight change was associated with mortality more than 50 years later. The Collaborative Perinatal Project (CPP) was a prospective US pregnancy cohort (1959–65). The CPP Mortality Linkage Study linked CPP participants to the National Death Index and Social Security Death Master File for vital status to 2016. Adjusted hazard ratios (HRs) with 95% CIs estimated associations between gestational weight gain and loss according to the 2009 National Academy of Medicine recommendations and mortality by pre-pregnancy BMI. The primary endpoint was all-cause mortality. Secondary endpoints included cardiovascular and diabetes underlying causes of mortality. Among 46 042 participants, 20 839 (45·3%) self-identified as Black and 21 287 (46·2%) as White. Median follow-up time was 52 years (IQR 45–54) and 17 901 (38·9%) participants died. For those who were underweight before pregnancy (BMI <18·5 kg/m2; 3809 [9·4%] of 40 689 before imputation for missing data]), weight change above recommendations was associated with increased cardiovascular mortality (HR 1·84 [95% CI 1·08–3·12]) but not all-cause mortality (1·14 [0·86–1·51]) or diabetes-related mortality (0·90 [0·13–6·35]). For those with a normal pre-pregnancy weight (BMI 18·5–24·9 kg/m2; 27 921 [68·6%]), weight change above recommendations was associated with increased all-cause (HR 1·09 [1·01–1·18]) and cardiovascular (1·20 [1·04–1·37]) mortality, but not diabetes-related mortality (0·95 [0·61–1·47]). For those who were overweight pre-pregnancy (BMI 25·0–29·9 kg/m2; 6251 [15·4%]), weight change above recommendations was associated with elevated all-cause (1·12 [1·01–1·24]) and diabetes-related (1·77 [1·23–2·54]) mortality, but not cardiovascular (1·12 [0·94–1·33]) mortality. For those with pre-pregnancy obesity (≥30·0 kg/m2; 2708 [6·7%]), all associations between gestational weight change and mortality had wide CIs and no meaningful relationships could be drawn. Weight change below recommended levels was associated only with a reduced diabetes-related mortality (0·62 [0·48–0·79]) in people with normal pre-pregnancy weight. This study's novel findings support the importance of achieving healthy gestational weight gain within recommendations, adding that the implications might extend beyond the pregnancy window to long-term health, including cardiovascular and diabetes-related mortality. National Institutes of Health. [ABSTRACT FROM AUTHOR]