Abstract:
The steroid hormone progesterone is considered indisPensible
for pregnancy - it is the 'hormone of pregnancy' as described
by corner (1928). It is generally agreed that the role of
progesterone in all species is to Prepare the endometrium for
pregnancy and to contribute to the maintenance of myometrial
quiescence from implantation to the end of Pregnancy. There
is however, a conflict of opinion concerning its role in
pregnancy termination. In some species, for example the
sheep, there is considerable evidence that progesterone
provides an important link between fetal cortisol and the
control of uterine activity. But in human pregnancy the
evidence is conflicting.
The present study investigates the role of progesterone in
the initiation of uterine activity in;
- late pregnant ehtes,
- early human pregnancy and
- the luteal phase of the human menstrual cycIe.
The study was designed following the development of a
3 B-nyaroxysteroid dehydrogenase (3 B-ttso) inhibitor
(Epostane) by Sterling Winthrop Research. In vitro,
Epostane acts comPetitively to inhibit the conversion of
pregnenolone to Progesterone. This provides a method of
investigating the role of Progesterone in the classical
manner - depressing the rate of secretion.
