Single midluteal progesterone assay in the management of ovulatory infertility.

A midluteal (five to ten days before the onset of the next period) single serum progesterone measurement, used routinely to assess luteal function, revealed, in 48 infertile women, values lower than 10 to 15 ng/ml. Clomid alone or with human chorionic gonadotropin (HGC) was used in their treatment. Twenty-six (58%) women successfully conceived on Clomid or Clomid and HCG. Progesterone measurements before and during treatment showed that values of midluteal progesterone increased from a pretreatment mean of +/- SD of 9.0 +/- 5.9 to 27.3 +/- 10.3 ng/ml during conception cycles. The single progesterone measurement at midluteal phase is a useful guide in the management of ovulatory infertility.