Children of older female mice more prone to heart problems

Particular changes in the placenta of older females can lead to heart problems in older sons according to a study, published in Scientific Reports, conducted on rats. The researchers discovered differences defined in the press release as “significant” regarding the development and growth of the fetus and its connection with the placenta according to its sex.

The researchers carried out experiments with pregnant female rats aged 3-4 months or 9.5-10 months. Older females had an age which, according to the researchers, may correspond to a human age of about 35 years which is considered a sort of “limit” beyond which one begins already to speak of “advanced maternal age.” The researchers found that for sons born to older mothers there were more likely to be heart problems and hypertension.

While with female fetuses the placenta showed no particularly negative changes in its structure and in its function, and in some cases, the same placenta provided more benefit to female fetuses in cases of older mothers than younger mothers. With male fetuses, this did not happen and the same changes in the placenta seemed to limit the growth of the fetus.

These findings could lead to “better management of human pregnancies and the development of targeted interventions to improve the long-term health of children born to older mothers,” explains Tina Napso, a Cambridge University researcher and one of the authors of the study.

This further study shows that the pregnancy of older mothers is more at risk than the pregnancy of younger mothers not only for the mother herself but also for the baby.

As Amanda Sferruzzi-Perri, researcher at the Center for Trophoblast Research at the same English university, explains, “With the average age of first pregnancy in women becoming ever higher, and especially in developed countries, it is very important to understand how age interacts of the mother and the sex of the child to determine the child’s pregnancy and health in old age.”