Effect of clomiphene citrate administration during the early luteal phase on the luteal function and pregnancy rate of women.

To study the effect of clomiphene citrate (clomiphene) administration during the early luteal phase of the menstrual cycle on the luteal function and the pregnancy rate in women, 75 infertile women who ovulated but did not conceive after clomiphene treatment during the early follicular phase and 6 normal cycling women were chosen. Clomiphene was administered orally to 35 of the 75 infertile women at a dose of 50 mg per day for 5 days from the second day of the rise in the basal body temperature (BBT) as well as during the follicular phase, while 40 control patients received clomiphene only during the follicular phase. In the test patients, the rate of pregnancy (25.7%) was significantly (p less than 0.05) higher than that of control patients (10.0%). On the 7th of the rise of BBT, the mean serum progesterone levels of the test patients and normal cycling women treated with clomiphene were significantly (p less than 0.05) higher than those of the control patients. However, the levels of serum estradiol, LH and FSH, the gonadotropin pulsatilities, and the pituitary responses to LH-RH in the test women were not significantly different from those of the control. These data suggest that, when administered during the early luteal phase, clomiphene may act directly on the ovary, enhancing the secretion of progesterone from the corpus luteum, and thereby increasing the rate of pregnancy in infertile women with clomiphene-induced ovulation.