Corpus luteum dysfunction: serum progesterone levels in diagnosis and assessment of therapy for recurrent and threatened abortion.

These studies were designed to show that properly timed measurements of serum progesterone (P) can be conveniently used in the diagnosis and treatment of patients with recurrent and threatened abortion. Luteal phase serum P levels between 2 and 10 ng/ml and serum P levels below 15 ng/ml in the first 10 weeks of gestation were considered diagnostic of corpus luteum (CL) dysfunction. Patients were treated with clomiphene, gonadotropins, and/or progesterone suppositories in order to correct serum P levels, thus elevating the serum P into the normal range. When treatment of patients with subnormal P levels resulted in normalization of serum P, successful pregnancies occurred. CL dysfunctions, either before or after conception, were found in eight of the nine patients with histories of recurrent spontaneous abortions. Correction of serum P was associated with successful pregnancy in these eight patients. Twelve patients with threatened abortion were also found to have subnormal serum P levels. Progesterone suppositories corrected the serum P levels in nine of the eleven patients treated, and none of these patients aborted. Serum P measurements provide a means for evaluation of CL function during early gestation. Management of patients with CL dysfunction can also be monitored with serial serum P measurements, provided that progesterone is the therapeutic agent rather than synthetic progestins.