Study Clarifies Obesity-Infertility Link

Being obese has long been linked to infertility in females, but researchers may have been wrong about how the link was forged, a new study suggests.

Doctors and scientists have thought that the fertility problems were caused by resistance to the hormone insulin. Chronically high levels of insulin often accompany obesity, eventually making muscles and other tissues impervious to the hormone’s signals.


A new study in mice shows that the pituitary gland, which helps regulate the release of fertility-associated hormones, remains sensitive to insulin. But in obese mice, insulin’s constant signaling to release the fertility hormones leads to an overabundance of those hormones, and consequently infertility, researchers report in the Sept. 8 Cell Metabolism.

The discovery firmly ties metabolism to fertility in an unexpected way and may have implications for treating women with a condition known as polycystic ovary syndrome, which is characterized by abnormal menstrual cycles and is often associated with obesity and type 2 diabetes...