Detection of subclinical abortion in infertile women by beta-hCG radioimmunoassay.

Serum hCG was measured by specific beta-hCG radioimmunoassay during the late luteal phase in 58 infertile women recording the basal body temperature. As control, serum hCG was also measured during the 5th to 17th day after the basal body temperature shift in 18 normal pregnancy. In all normal pregnancy cases serum hCG was detected after the 9th day from basal temperature shift. Serum hCG was detected during the late luteal phase in 6 cases, including 2 cases succeeded in pregnancy in corresponding cycle, out of 58 infertile women. In spite of the hCG detection, the hyperthermic phase on BBT chart was not significantly prolonged in remaining 4 cases, in which the next menses took place as usual. Thus, so called subclinical abortion was suspected in these 4 cycles. This result suggests subclinical abortion might occur in infertile women. When hCG is detected during the late luteal phase, intensive treatment for the defective luteal function may salvage the endangered pregnancy. Since the incidence of hCG detection in this study was rather smaller than the previous reports, the major portion of causes of infertility might exist earlier or around the time of implantation of fertilized ovum.