While it doesn't provide answers as to how infertility in women may be reversed, results form a recent study offers an explanation why infertility drugs may not work in some women. In the August issue of Endocrinology, researchers report that in mice that were genetically engineered to lack estrogen receptor beta, fertility drugs did not improve ovulation rates.

"If the results from this animal study are found to be applicable to humans, a simple blood test will be able to provide enough information to determine if a genetic mutation may be altering the function of the estrogen receptor beta. The results of this blood test, coupled with information from other medical tests and evaluations conducted by the physician, will help diagnose infertility and better determine treatment options."

See NIH press release here. Or the full text article here (requires subscription).