Plasma progesterone and oestradiol estimations in the diagnosis and treatment of luteal insufficiency in menstruating infertile women.

Plasma progesterone and estradiol estimations were performed in the diagnosis of 299 unselected menstruating patients complaining of infertility. Plasma progesterone levels were measured during the luteal phase of the cycle 5-10 days before the onset of menstruation. Plasma estradiol levels were recorded during the presumptive preovulatory and midluteal phase of the cycle in 46 patients. 145 patients had obvious nonhormonal causes of infertility - tubal occlusion endometriosis chronic cervicitis and infertile husbands. Their mean midluteal plasma progesterone was 14.5 + or - 4.4 ng/ml. Of these patients 21 had midluteal levels of progesterone which were deficient (less than 10 ng/ml). 154 patients had unexplained infertility. In this group the mean midluteal plasma progesterone was 11.9 + or - 5.3 ng/ml significantly lower than the nonhormonal subgroup (p less than .001). 61 of these patients with midluteal levels considered to be deficient underwent clomiphene therapy. 75 cycles from 64 patients were analyzed. There was a 2-fold increase in plasma progesterone concentration 17.9 + or - 5 ng/ml) as compared with pretreatment values. 18 patients had poor response and were further treated with human chorionic gonadotropin (HCG). Midluteal progesterone levels increased to 16.9 + or - 7.8 ng/ml. 3 patients were resistant to stimulation. There were 32 conceptions in 30 women on clomiphene alone; 9 pregnancies occurred in clomiphene plus HCG treated cycles. The overall success rate was 56%. Plasma estradiol estimations during nontreatment cycles were 216 + or - 63 pg/ml in normal cycles and 176 + or - 63 pg/ml in cycles with luteal deficiency. Estimations made after clomiphene therapy showed values significantly higher (p less than .05) than during spontaneous normal cycles. HCG treatment also gave significantly higher results (p less than .01). These findings support the view that luteal deficiency reflecting defective ovulation is an important cause of otherwise unexplained infertility.