Greater Estrogen In Postmenopausal Obesity Blocks FSH Production.(follicle-stimulating hormone )

2001 MAY 17 - (NewsRx Network) -- by Susan Hasty, senior medical writer - Scientists working in Mexico have shown that greater estrogen levels in obese, postmenopausal women are responsible for their lower follicle-stimulating hormone (FSH) levels.

FSH is the hormone that stimulates hair follicle development and ovulation, among other things. Because fat cells store estrogen, and estrogen suppresses the production of FSH, Juan M. Malacara and colleagues at the University of Guananjuato, Gito, hypothesized that greater estrogen levels in postmenopausal obese women accounted for lower FSH levels than are normally observed in Jean postmenopausal women. To test this hypothesis and uncover any relationship this process may have to insulin resistance, the Malacara research team set up an experiment with four groups of obese (body mass index, BMI [greater than or equal to] 29) and lean (BMI [less than or equal to] 29), postmenopausal women.

The first group was treated with 400 mg of the insulin sensitizer troglitazone (TG) daily for two weeks, and 150 mg of clomiphene citrate (CC, an analog of the nonsteroidal estrogen, chlorotrianisene) was added to the treatment for the second week, the researchers reported. The second group was treated with 150mg CC daily for one week. The third group received 1,000 mg of metformin (MET), an oral hypoglycemic agent, daily for two weeks, and 120 mg of raloxifene (RAL, a selective estrogen receptor modulator) was added at the start of the second week. The fourth group got 120 mg RAL for a week, Malacara and coworkers said.

Blood samples were taken periodically to test for FSH, lutenizing hormone (LH), leptin, dehydroepiandrosterone sulfate (DHEAS), glucose, insulin, and insulin resistance (HOMA-IR) levels ("Gonadotropins at menopause: the influence of obesity, insulin resistance, and estrogens," ...