A possible role of vasopressin in the control of ovarian activity

Simultaneous vasopressin concentrations in the preovulatory follicular fluid and plasma were determined for 12 patients with tubal infertility. Nine of the patients received clomiphene citrate, 100 mg daily, on cycle days 5 through 9. On the 11th day of the cycle, 5000 IU of hCG was given intramuscularly. At laparoscopy the ovarian follicles were aspirated 36 hours after hCG injection. For three patients the follicle aspiration was performed at laparotomy during the 11th-14th days of the normal cycle. In all these cases the vasopressin concentration in plasma exceeded markedly that in the follicular fluid. In the patients undergoing laparoscopy the vasopressin concentration in the follicular fluid was 11.2 +/- 8.2 pg/ml and that in plasma 17.3 +/- 22.0 pg/ml. It is most probable that the hormone enters fluid from the plasma.