Sons of obese mothers at increased health risk in adulthood

Males born to obese women are more likely to be overweight at birth and develop metabolic complications in later life, including liver disease and diabetes.

A new study led by University of South Australia (UniSA) researchers explores the impact of maternal obesity on fetal liver androgen signaling.

Male fetuses of obese pregnant women have different signals that are activated by male sex hormones in the liver, which encourages them to prioritize growth at the expense of their health. The androgens give men their male characteristics and are crucial in their development, but if there are too many, male fetuses grow too large, causing not only problems at birth but also impacting liver function as an adult.

Female fetuses, on the other hand, exposed to excess testosterone from an obese pregnancy are wired to switch off the androgen pathway in the liver, restricting their growth and lowering the risks of metabolic disorders in adulthood.

"We know there are sex differences in metabolic disorders in later life in response to maternal obesity," says Dr Ashley Meakin, a researcher at UniSA.

"Men are more prone to non-alcohol fatty liver diseases and diabetes as an adult if their mother is obese during pregnancy and their birth weight is above 4 kg (9 lb 15 oz). They are genetically wired to prioritize androgens because it supports the development of male characteristics -- including size -- but too much androgen is bad."

Dr Meakin found that in the intervening period, supplements that address nutritional imbalances in pregnancy could provide the fetus with the best chance of optimal development.

"As a society, we urgently need to address obesity. If children were taught early on about the importance of healthy eating, it would carry through into adulthood, including during pregnancy, where the right nutrition is so important," he concluded.

Reference: Ashley S. Meakin, Peter W. Nathanielsz, Cun Li, Vicki L. Clifton, Michael D. Wiese, Janna L. Morrison. Maternal obesity impacts fetal liver androgen signaling in a sex-specific manner. Life Sciences, 2024; 337: 122344 DOI: 10.1016/j.lfs.2023.122344