Cycle abnormalities in infertile women with regular menstrual cycles: effects of clomiphene citrate treatment

To investigate the incidence and nature of cycle abnormalities and the effect of clomiphene citrate (CC) treatment in women with apparently ovulatory cycles and unexplained infertility.

Nonrandomized, open study of patients before and during treatment.

The Reproductive Medicine Clinic of a District General Hospital.

Thirty-five women with regular, apparently ovulatory menstrual cycles and unexplained infertility.

Detailed ultrasound and hormonal cycle tracking was performed before and during treatment with CC.

Serial ultrasound scans and measurements of serum LH, FSH, E2, and P.

Before treatment, 54% of cycles were uniovulatory, 40% were characterized by cyst formation, and 6% were characterized by poor follicular growth. Fifty-one percent of pretreatment cycles had normal hormone profiles, 31% had defective luteal phases, 14% had increased early follicular phase serum FSH levels, and 9% had increased early follicular phase serum LH levels. Treatment with CC reduced the incidence of cyst formation to 9% and the incidence of luteal phase defects to 3%. However, 28% of CC-treated cycles showed ultrasound features of overstimulation and 51% had high follicular phase E2 peaks so that only 34% of CC-treated cycles had normal hormone profiles.

Cycle abnormalities are common in unexplained infertility. The incidence of cyst formation and luteal phase defects, the most common abnormalities in this group, is reduced by CC treatment.