SAN ANTONIO — Robin Khadduri gets monthly shots of a drug that blocks the male hormone testosterone and is often used to treat prostate cancer.

But Khadduri doesn't have a prostate or much testosterone either. She and many other young women are getting the drug for breast cancer as part of a super-hormone treatment that new research suggests may improve their survival odds.

This chemical equivalent of ovary removal has one big advantage over surgery: it's not permanent, so it may preserve a woman's ability to have children.

In premenopausal women, the drugs suppress the pituitary gland, which produces hormones that control the ovaries and cause a woman to have a period every month. Side effects of this induced early menopause are similar to those of natural menopause — hot flashes, night sweats, etc., according to new research presented at the recent San Antonio Breast Cancer Symposium. Women like Khadduri, who fear cancer's return, consider that a small price to pay.

The drugs include triptorelin, goserelin, leuprolide and buserelin, sold as Lupron, Zoladex, Prostap and other brands.

Such drugs have been around for 20 years and are used more in Europe than in the United States, where attention has focused more heavily on chemotherapy, said V. Craig Jordan of Fox Chase Cancer Center in Philadelphia, the scientist who developed tamoxifen, a mainstay hormone drug for preventing cancer recurrence.

"This has been like tumbleweed slowing gaining momentum," he said of ovarian suppression.

The drugs are most often used in two situations:

n As an alternative to chemotherapy for women who have had surgery for small, hormone-fueled tumors and are considered at relatively low risk for recurrence.

• As a way to keep the ovaries suppressed in women whose periods return after temporarily stopping during chemotherapy.

"They call it 'chemopause,"' said Khadduri, who is getting triptorelin shots now. The 37-year-old mother of three from Needham, Mass., was found in January to have two small tumors that had spread to at least one lymph node but not extensively.

"The thing I liked about it is, it was not permanent," she said of the treatment. "It wasn't like I was having surgery to have my ovaries removed. If the side effects were too much, I could stop."