Abstract:
The effect of a pharmacologic dose of synthetic oxytocin on corpus luteum function was evaluated in rhesus monkeys during normal menstrual cycles, or during menstrual cycles in which the corpus luteum was concomitantly stimulated by injections of human chorionic gonadotropin (hCG). Oxytocin administered by intramuscular injection at a total dose of 4.5 milligrams (2250 I.U.) on Day +6 of the normal luteal phase (Day 0 is the day of the midcycle LH surge) did not change the concentrations of progesterone in the peripheral serum of monkeys or alter the duration of the luteal phase. The same dose of oxytocin, administered to monkeys on Day 22 of menstrual cycles in which hCG was also given on Days 20-22, caused a small, but statistically significant, reduction in serum progesterone values. The results indicate that oxytocin does not alter luteal life span or markedly change blood progesterone concentrations in primates.
