Women might reconsider having another child after reading this study.
Unless, of course, they want one.
After all, women are familiar enough with getting judged by their appearance to shrug off this new research; which suggests that if they stick to having one or two children it will help preserve their looks.
The study, where over 500 people judged photos of post-menopausal women, found those with smaller families looked more attractive.
Women were split into three categories, depending on the number of children they'd had: 1-2, 4-5 and 7-9 children.
Those with 7-9 children were judged to look less attractive, older and less healthy.
The study authors wrote:
We have shown that post-menopausal women who had fewer children were judged as more attractive, younger and healthier than women with more children, by both men and women.
In the paper, the researchers theorised that this was thanks to the strain on the body from pregnancy and breastfeeding. They wrote:
Mechanisms behind the observed variation in facial appearance are not known but higher levels of oxidative stress among women with high parity may explain their faster aging and lower attractiveness in older age.
These results suggest that costs of reproduction might affect women's physical appearance.
Oxidative stress is an imbalance between the production of free radicals - aka atoms with an odd number of electrons - and the body counteracting them with antioxidants. Scientists don't yet know what causes ageing, though oxidative stress may play a role.
Last year, a Yale University study found childbearing can cause accelerated ageing. After testing 100 post-menopausal women, it found that those who had experienced more pregnancies had higher levels of a biomarker for accelerated ageing.
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