The secretion of human chorionic gonadotropin-like substance in women employing contraceptive measures

Abstract

To study the secretion pattern of a hCG-like substance (hCG') in normal women and those employing contraceptive measures, we assayed daily urine concentrates by RIAs using an anti-hCG beta-COOH-peptide serum and an anti-hCG serum to monitor hCG' and human LH (hLH), respectively. In eight cycles of four normal women, urinary hCG' was within the normal range (less than 100 ng/day), except that four samples in two women had marginal elevations of hCG' during the menstrual or premenstrual period, but not at the time of the midcycle hLH surge. Among seven cycles from three intrauterine device (IUD) users, six showed midcycle hLH surges, and in five, hCG' was prominent (0.17-3.6 micrograms/day) in the late luteal phase. In eight cycles of women ingesting steroid contraceptives on a conventional schedule, hCG' was found during the premenstrual and menstrual intervals. The pattern of hCG' secretion was episodic, and hCG' levels were in the range of 0.3-1.8 microgram/day. It was notable that hCG' was excreted at the highest levels during intervals when ingestion of steroids was withheld. These findings suggest that contraceptive steroid hormones may modulate pituitary hCG' secretion. From gel high pressure liquid chromatographic studies, the immunoactive hCG' detected in urinary extracts from normally cycling women and IUD users had a molecular size larger than hCG beta and hLH, but was slightly smaller than hCG (lot CR119). The hCG' identified in these eluents is unlikely to be a subunit of hCG. On the other hand, the immunoactive hCG' in the urinary extracts from oral contraceptive users was mainly the hCG beta-subunit-like substance. Both hCG alpha and hCG beta immunoactive substances were heterogeneous in size in contrast to those found in normally cycling women and IUD users. In summary, the hCG' excretion pattern was different in menstrual and postmenopausal women, and hCG' identified in these subjects was heterogeneous.

PIP: To study the secretion pattern of an hCG-like substance (hCG') in normal women and those employing contraception, the authors assayed daily urine concentrates by radioimmunoassays using an anti-hCGbeta-COOH-peptide serum and an anti-hCG serum to monitor hCG' and human luteinizing hormone (hLH), respectively. In 8 cycles of 4 normal women, urinary hCG' was within the normal range (100 ng/day), except that 4 samples in 2 women had marginal elevations of hCG' during the menstrual or premenstrual period, but not at the time of the midcycle hLH surge. Among 7 cycles from 3 IUD users, 6 showed midcycle hLH surges, and in 5, hCG' was prominent (0.17-3.6 mcg/day) in the late luteal phase. In 8 cycles of women ingesting steroid contraceptives on a conventional schedule, hCG' was found during the premenstrual and menstrual intervals. The pattern of hCG' secretion was episodic and hCG' levels were in the range of 0.3-1.8 mcg/day. It was notable that hCG' was excreted at the highest levels during intervals when steroid ingestion was withheld. These findings suggest that contraceptive steroids may modulate pituitary hCG' secretion. From gel high pressure liquid chromatographic studies, the immunoactive hCG' detected in urinary extracts from normally cycling women and IUD users had a molecular size larger than hCGbeta and hLH, but was slightly smaller than hCG (lot CR119). The hCG' identified in these eluents is unlikely to be a subunit of hCG. On the other hand, the immunoactive hCG' in the urinary extracts from OC users was mainly the hCG beta-subunit-like substance. Both hCGalpha and hCGbeta immunoactive substances were heterogeneous in size in contrast to those found in normally cycling women and IUD users. In summary, the hCG' excretion pattern was different in menstrual and postmenopausal women, and hCG' identified in these subjects was heterogeneous.