Eighty-seven anovulatory patients were treated with clomiphene citrate (CC) to induce ovulation in 414 cycles. Clomiphene citrate was initiated randomly on the 2nd, 3rd, 4th, or 5th day of the menstrual cycle to evaluate the effectiveness of therapy. The results of therapy were assessed in terms of ovarian response and pregnancy outcome. Ovarian response was evaluated employing basal body temperature (BBT) to define follicular, luteal, and cycle lengths, and a midluteal serum progesterone (P) level and the integrated luteal P to define luteal adequacy. Pregnancy outcome was evaluated in the categories of total pregnancy, live birth, first trimester abortion, and fecundity rates. There were no significant differences noted between the groups who started CC on the 2nd, 3rd, 4th, or 5th day of cycle in terms of anovulation rates (12% to 21%), luteal dysfunction (28% to 39%), and normal ovulation rates (42% to 57%). Pregnancy was achieved in 31% (n = 27/87) of patients with a spontaneous abortion rate of 19% (n = 5/27). The fecundity rates ranged between 5.7% and 9.4%. Pregnancy outcomes also were not significantly different between the groups. Significantly shorter luteal phase length and longer follicular phase length were observed in the cycles with luteal dysfunction. The luteal progesterone parameters, including midluteal serum P concentration, the integrated luteal P, and the luteal P amplitude were significantly lower in the cycles with luteal dysfunction.