Pregnancy and breastfeeding linked to higher cognitive ability in postmenopausal women

Pregnancy and breastfeeding are linked to stronger cognition in postmenopausal women, a long-term study suggests.

Greater cumulative time spent pregnant and time spent breastfeeding correlated with higher overall scores in the study, including verbal and visual memory, in later life.

Researchers analysed annual assessments of more than 7,000 women aged about 70 for up to 13 years using data from the Women’s Health Initiative Memory Study and the Women’s Health Initiative Study of Cognitive Aging.

On average, those who were pregnant for around 30.5 months were expected to have a 0.31 per cent higher global cognition score than those who had never been pregnant.

A lifetime average of 11.6 months of breastfeeding was linked to a 0.12 per cent higher global score.

Each additional month spent pregnant was associated with a 0.01-point rise in overall ability.

Each extra month of breastfeeding showed the same increase, and a 0.02-point gain in verbal and visual memory. Although small, these effects are similar to known protective factors such as not smoking and high physical activity.

The work was led by Molly Fox, an anthropology professor at the University of California, Los Angeles.

Fox said: “Any ways in which we can focus public health outreach or clinical interventions towards higher-risk populations leads to more effective and efficient efforts.”

Participants who had ever been pregnant scored, on average, 0.60 points higher than those who had never been pregnant.

Those who had breastfed scored 0.19 points higher overall and 0.27 points higher for verbal memory than those who had never breastfed.

Women are disproportionately affected by Alzheimer’s disease, a progressive condition that impairs memory and thinking skills, and this is not fully explained by life expectancy differences.

The authors say biology and social factors may both play roles.

They noted that more adult children could contribute to cognitive health by buffering stress, supporting wellbeing or encouraging healthy behaviour.

“If we can figure out, as a next step, why those reproductive patterns lead to better cognitive outcomes in old age, then we can work towards figuring out how to craft therapies, for example, new drugs, repurposed drugs or social programmes, that mimic the naturally occurring effect we observed,” said Fox.

The study team is now working to identify the mechanisms that link reproductive histories to cognitive resilience.