Number of pregnancies linked to Alzheimer’s risk

American Academy of Neurology: Differential effects of completed and incomplete pregnancies on the risk of Alzheimer disease

A new study by researchers in Korea and the US suggests a link between number of pregnancies and the risk of Alzheimer’s disease. The research is published today (Wednesday 18 July) in the Journal of The American Academy of Neurology.

Dr Carol Routledge, Director of Research of Alzheimer’s Research UK, said:

“Nearly two thirds of people living with dementia in the UK are women, and while differences in life expectancy account for some of this disparity, researchers don’t fully understand why diseases like Alzheimer’s have a greater impact on women.

“Pregnancy is a distinctive experience of women and this study highlights a potential link between the number of children that women have and the risk of Alzheimer’s disease. Only women who had given birth to five or more children were found to have a higher risk of Alzheimer’s and the study doesn’t tell us what the reason for this link might be.”

“Pregnancy is a complex biological process which involves changes in the levels of several hormones including the female sex hormone oestrogen. This study lends support to the idea that oestrogen or other hormones may have an impact on Alzheimer’s risk, but we don’t understand the nature of this relationship.

“There will be a wide range of factors associated with having a large number of children, and while the researchers tried to take social and economic status into account in their analysis, it is impossible to rule out non-biological causes for this apparent link.”