Antimullerian hormone and obesity: insights in oral contraceptive users

Abstract

Background: The study was conducted to examine the impact of oral contraceptives (OCs) on serum antimullerian hormone (AMH) levels by obesity status in reproductive-age women.

Study design: Ovulatory women, ages 18-35 years, of normal (<25 kg/m(2); n=10) and obese (>30 kg/m(2); n=10) body mass index (BMI) received a low-dose OC (20 mcg ethinyl estradiol/100 mcg levonorgestrel) for two cycles. Serum samples obtained at several time points during active pill use and hormone-free intervals were analyzed for AMH, follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol and inhibin B.

Results: AMH levels did not differ by OC cycle day in either BMI group. On average, AMH levels were 34% lower in the obese group (2.9+/-2.1 vs. 4.4+/-1.8 ng/mL, p<.05). Modeling to determine differences in AMH throughout the cycle based on obesity status demonstrated significantly lower levels (p<.05), whereas serum AMH, FSH, LH, estradiol and inhibin B levels revealed no correlations when all time points were included.

Conclusions: In reproductive-age women, serum AMH levels do not appear to fluctuate during OC use, but AMH levels are significantly lower in obese women. Lower levels do not appear to be due to differences in gonadotropin levels or ovarian activity.

Fig. 1

Hormone levels during OC use in obese and normal groups. Days 1–28 occur during the first cycle of OCs (days 22–28 are the hormone free interval) and days 29–49 in the second cycle of OCs. A) AMH levels. Normal weight subjects are shown in solid line box plots and obese in dashed line box plots. Boxes represent the interquartile range (25%–75%), center lines the median, and points outliers. B) FSH, inhibin B, and estradiol levels. FSH levels are depicted with solid lines, inhibin B with dots, and estradiol with dashes. The obese group is depicted with open triangles and the normal group with closed circles. Points depict mean hormone levels.

Fig. 1

Hormone levels during OC use in obese and normal groups. Days 1–28 occur during the first cycle of OCs (days 22–28 are the hormone free interval) and days 29–49 in the second cycle of OCs. A) AMH levels. Normal weight subjects are shown in solid line box plots and obese in dashed line box plots. Boxes represent the interquartile range (25%–75%), center lines the median, and points outliers. B) FSH, inhibin B, and estradiol levels. FSH levels are depicted with solid lines, inhibin B with dots, and estradiol with dashes. The obese group is depicted with open triangles and the normal group with closed circles. Points depict mean hormone levels.