Temporary increase of FSH levels in healthy, nulliparous, young women after cessation of low-dose oral contraceptive use

• PIP: At the University Hospital in Lund, Sweden, researchers grouped healthy nulliparous women aged 19-25 into current, former, and never users of low-dose combined oral contraceptives (OCs) to examine the effect of the OCs on the levels of follicle stimulating hormone (FSH) and luteinizing hormone (LH). The subjects were from two independent samples. Based on the day the blood was sampled, their hormone level readings were divided into follicular and luteal phases. Former OC users had higher FSH levels than did never users, regardless of menstrual cycle phase (group 1: 1.9 vs. 1.6 mcg/l for follicular phase, 1.6 vs. 1 mcg/l for luteal phase; p = 0.004) (group 2: 2.05 vs. 1.7 mcg/l, 1.55 vs. 1.25 mcg/l; p = 0.028). The transient increase of FSH levels appeared to peak 12 months after the women stopped using the OC. The researchers found that the temporary increase in FSH levels was still significant after they excluded eight women with low progesterone levels (10 nmol/l in luteal phase and 3.5 nmol/l in follicular phase) and adjusted for age (p = 0.015). LH levels were much higher in former users than never users in the first sample (1.6 vs. 1 mcg/l for follicular phase, 1.8 vs. 1.15 mcg/l for luteal phase; p = 0.014), but not in the second sample. Smoking and time since awakening had no effect on FSH and LH levels. Present users experienced suppressed FSH and LH levels. These findings indicate that former OC users experience a rebound-like phenomenon in FSH levels. Since the sample size was small and only one blood sample was taken from each woman at each of the sampling times, the researchers caution that these findings are preliminary and unconfirmed.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Reproduktionsmedicin och gynekologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Obstetrics, Gynaecology and Reproductive Medicine (hsv//eng)

Keyword

LH

FSH

low-dose oral contraceptives

nulligravid women

Publication and Content Type

art (subject category)

ref (subject category)