Obesity affects circulating estradiol levels of premenopausal hirsute women receiving leuprolide acetate depot.

OBJECTIVE

To investigate the effect of premenopausal obesity on circulating levels of estradiol, estrone, free testosterone, androstenedione, DHEAS, and immuno- and bioactive FSH and LH.

SETTING

University clinic.

PATIENTS AND INTERVENTIONS

Premenopausal hirsute women, four obese and four nonobese, received leuprolide acetate depot [LD in monthly injections (7.5 mg, i.m.)] until estradiol levels decreased to menopausal values; single monthly injections of 15 and then 22.5 mg LD were given if estradiol remained higher than menopausal after 3 months.

RESULTS

Estradiol levels of nonobese women reached menopausal values with the 7.5-mg dose, and those of obese women were not significantly reduced with any LD dose. Estrone declined to menopausal levels with 7.5 mg LD, while free testosterone and androstenedione were diminished with 7.5 mg, but not further with 15 or 22.5 mg. Bioactive LH and the bioactive/immunoactive LH ratio were maximally suppressed with 7.5 mg LD; however, LD did not change bioactive FSH levels or the bioactive/immunoactive FSH ratio. These findings were not related to adiposity.

CONCLUSIONS

Premenopausal obesity affects circulating estradiol levels of hirsute women receiving LD. The effect does not reflect weight-related differences in circulating levels of androgens or bioactive gonadotropins. Premenopausal adiposity in hirsute women may influence the estrogenic milieu associated with desensitization to GnRH.