Reproductive History and Cognitive Aging: The Bogalusa Heart Study

Although it has become increasingly clear that pregnancy-related health predicts later-life cardiometabolic health, the relationship between reproductive history and cognitive health is less frequently studied. Although some research has identified associations between parity or hypertensive disorders of pregnancy and cognitive changes, the evidence is mixed.

To examine the association between reproductive history and midlife cognition in a community-based population.

Seven hundred and thirty midlife women in the Bogalusa Heart Study completed a brief cognitive battery (memory, attention, executive function, and processing speed) and were interviewed about their reproductive history. Reproductive history (parity, age at first pregnancy, and breastfeeding) and pregnancy complications (low birthweight, preterm birth, hypertensive disorders, and miscarriage) were examined as predictors of cognitive function, with adjustment for potential confounders.

Nulliparous women had an overall lower cognitive score (adjusted beta -1.50, standard error [SE]: 0.41). Adolescent birth was associated with a somewhat better performance on the Trail Making Test (beta -0.31, SE: 0.15 for birth <16 years), while high parity was not strongly associated with any of the cognitive measures. History of pregnancy complications was not strongly associated with cognitive function, whereas history of miscarriage was associated with better cognitive function, as was a history of breastfeeding (beta overall score 0.90, SE: 0.29), particularly noticeable for semantic memory and in those with more total breastfeeding time (beta for overall score among those with >24 weeks lifetime breastfeeding, beta 1.21, SE: 0.44).

Nulliparity and breastfeeding are associated with midlife cognition in women. Future studies should examine possible mechanisms by which these associations are created.