Effects of previous use of oral contraceptives on early follicular phase follicle-stimulating hormone.

OBJECTIVE

To determine if previous oral contraceptive (OC) use is associated with changes in early follicular phase FSH, LH or E2.

DESIGN

A cross-sectional study examining determinants of early follicular phase hormone levels.

SUBJECTS: Subjects included 106 premenopausal women with a family history of ovarian cancer and 116 premenopausal women without this history who were not taking OCs currently. All subjects completed a structured interview and gave an early follicular phase blood sample.

SETTING

Gynecologic Epidemiology Center and Familial Ovarian Cancer Research Center.

MAIN OUTCOME MEASURES: Follicle-stimulating hormone, LH, and E2 were measured in early follicular phase plasma samples.

RESULTS

Recency or length of prior OC use did not affect early follicular phase LH or E2 levels. Length of OC use did not affect FSH levels in all subjects; but lower levels of FSH were observed in women over age 45 who had used OCs for > 5 years. Early follicular phase FSH is lower in women with OC use within the past 5 years compared with women with more remote use or who never used OCs, after adjustment for age, smoking, and family history status.

CONCLUSIONS

Past use of OCs may have a residual effect on basal FSH levels in women not using them currently that depends on recency of use and to a lesser extent duration of prior use.