QUALITATIVE CHANGES IN URINARY GONADOTROPHINS IN HUMAN PREGNANCY DURING THE PERIOD OF RAPID INCREASE IN HORMONE TITER1

Abstract

Quantitative and qualitative analyses (mouse uterine and hypophysectomized rat ovarian responses, respectively) were made of the hormone content of urines from 16 cases of pregnancy. The titer of gonadotropin in the urine, measured by the response of the mouse uterus, rose slightly by the 7th- 18th days post-ovulation, the daily excretion being between 90 and 100 mouse uterine units (MUU) (or IU). After this time the amt. began to rise with extreme rapidity, reaching values of 400,000 MUU or more by 35 days. This abrupt increase in output occurs with remarkable constancy in different patients, when increases are plotted in terms of the post.ovulatory period, thus eliminating the variability due to different lengths of menstrual cycle. Tested by the response of the hypophysectomized immature female rat''s ovaries, the urine from the earliest period of pregnancy caused only interstitial tissue repair. This hormonal effect was 1st seen on the 12th day after ovulation (cycle day 26). The urinary concentrates from specimens obtained after the 33d day of pregnancy caused stimulation of follicular growth in addition to repair or hypertrophy of the interstitial cells. Pregnancy urine from this period also stimulated the thyroids of the hypophysectomized test animals.