Association of Life's Crucial 9 with self-reported reproductive lifespan and pregnancy loss: the National Health and Nutrition Examination Survey 2007-2018.

Objectives: This study explores the relationship between Life's Crucial 9 (LC9), a recently updated cardiovascular health (CVH) assessment tool by the American Heart Association (AHA), and self-reported reproductive lifespan, as well as pregnancy loss history.

Methods: The analysis utilized data from 2,405 postmenopausal women in the United States collected from the National Health and Nutrition Examination Survey (NHANES) database between 2007 and 2018. LC9 scores, ranging from 0 to 100, were calculated based on AHA's definitions and divided into health behavior and health factor components. The association between LC9 scores, reproductive lifespan, and the self-reported incidence of pregnancy loss was evaluated using weighted multivariable linear and Poisson regression models.

Results: Individuals in the highest tertile of the LC9 score experienced a significantly higher age at menopause (0.034 y, [0.009, 0.059)]) and a longer reproductive lifespan (0.045 y, [0.004, 0.085]) compared with those in the lowest tertile. Furthermore, we identified a linear association between the LC9 score and reproductive lifespan. The positive correlation between the LC9 score and reproductive lifespan was notably stronger among non-Hispanic Whites. For self-reported pregnancy loss, the fully adjusted relative prevalence (95% CI) for the LC9 score was 0.699 (0.436-1.120), which remained consistent after further adjustment for reproductive lifespan. However, this association did not reach statistical significance, indicating that there may not be a strong relationship between LC9 scores and pregnancy loss in this cohort.

Conclusions: Our study indicated that a higher LC9 score could potentially extend women's reproductive lifespan and enhance reproductive health, although no significant association was found with pregnancy loss in this population.