Ovulation timing by a radioreceptor assay for human luteinizing hormone

Since predetermination of ovulation would be helpful in treatment of sterility, a quick, sensitive, and specific radioreceptor assay (RRA) for measurement of actual LH concentrations in human serum has been developed. Using partially purified membrane receptors from bovine testes, our assay system enabled precise measurement of LH within 4 hours. The detection limit of the present method is 0.78 ng LER 960/ml serum. The method was used to detect ovulation during four observation cycles each in eleven women who were undergoing treatment for infertility, such as recommended intercourse or artificial insemination because of reduced fertility of their husbands. In all women ovulations could be predicted by LH surge and were verified by laparoscopy within 36 hours. Insemination was carried out at the time of the characteristic increase of LH values around mid-cycle. Pregnancy occurred in three women during the observation period.