The relationship of early follicular phase serum LH and pregnancy rates in women with regular menses

Objective: To investigate the relationship of early follicular phase serum LH levels and pregnancy rates in ovulatory women with regular menstrual cycles. Methods: One hundred consecutive couples seeking help for infertility who had bilateral tubal patency, a minimum motile sperm density of 2.5 million/mL, and regular menstrual cycles were enrolled in the study. Baseline serum measurements of LH, FSH, and testosterone were obtained before treatment. Patients were treated with clomiphene citrate, human menopausal gonadotropin, or progesterone supplementation, as needed. Treatment continued for 6 months or until conception occurred. The 6-month pregnancy rates were correlated with baseline early follicular phase serum levels and age. Results: The 6-month viable pregnancy rates did not decrease with an increase in baseline LH serum levels; they were 50% if LH was 10 mIU/L or less, 15.3% if LH was 11-20 mIU/mL, and 71.4% if LH was more than 20 mIU/mL. The 16.7% pregnancy rate in women whose baseline FSH exceeded 25 mIU/mL was significantly lower than the 56.3% rate in women whose FSH was 25 mIU/mL or lower. The pregnancy rates also declined significantly with age. When we controlled for age, FSH did not have an independent effect on conception rates. Conclusion: Early follicular phase serum levels of LH were not associated with pregnancy rates in infertile ovulatory women who were treated with progesterone in the luteal phase when needed. However, early follicular levels of FSH and age at treatment were found to be related to pregnancy rates.