PROGESTERONE ADVANCEMENT OF OESTROGEN-INDUCED LUTEINIZING HORMONE RELEASE DURING THE MID-FOLLICULAR PHASE IN NORMAL CYCLIC WOMEN

Abstract

The influence of small amounts of progesterone on the timing of the estrogen-induced LH [luteinizing hormone] surge in normal cyclic women was studied. Results were consistent with the observations of Leyendecker, Wildt, Gips and Nocke (1975) on the augmentative effect of progesterone on LH release in response to estrogen. Parallel data on FSH [follicle-stimulating hormone] release, which have not previously been described in women treated with both steroids were reported. Although in normal cyclic women the LH surge at mid-cycle is principally induced by the preceding rise in estrogen, the results suggest that the slight increase in progesterone observed at the LH peak (Abraham et al. 1972; Thorneycroft et al. 1974) may play a role in controlling the timing and duration of the LH peak.