Transient luteolytic effect of prostaglandin F2alpha in the human.

Abstract

13 nonpregnant volunteers were infused with 50 mg/minute of PGF2alpha for 8 hours on selected days of the luteal phase to study hormonal patterns. Using the onset of menstrual bleeding to indicate the duration of the luteal phase a 1-3 day decrease was observed in 10 subjects no changes in luteal duration in 2 subjects and an increase in luteal duration in 1 subject. All volunteers showed a decrease in progesterone values during the 8 hour infusion ranging from 23.5-69.8% of the baseline value; however no consistent difference was seen at 24 hours. Observations of estrone and estradiol levels revealed no consistent pattern. These results demonstrate convincing evidence of at least a transient effect of PGF2alpha on the steroidogenic mechanism of the human ovary. Since PG affected progesterone but not estrogen biosynthesis and release a direct effect upon the granulosa cells or its blood supply must be postulated. Why PGF2alpha administration decreases progesterone production but does not affect estrogen synthesis is still not clear; it seems however that attempting to produce luteolysis by systemic PG administration is impractical.