This paper explores the effects of prostaglandins (PGs) on the Fallopian tubes and on the uterus. In vitro experimentation has shown that PGE1 and PGF2alpha stimulate the longitudinal muscle of the tubes, while, on the nonpregnant uterus, PGEs diminish the tonus of the muscle and PGFs stimulate it. The physiological action of PGs on the nonpregnant uterus is unclear; it is impossible to affirm or to deny that PGs contained in the sperm exercise an action on the female genital apparatus. The pregnant uterus, on the other hand, is stimulated by PGEs and by PGFs in vitro and in vivo, according to dosage and throughout the pregnancy. It is possible that PGs, which have been found in the amniotic fluid during labor, physiologically contribute to induction of labor. Thus, PGEs have already been used intravenously in induction of labor at term, at an average dose of 463 mcg, and with an average induction-delivery time of 7.9 hours. In certain cases PGs seem to be more effective than oxytocin. PGE2 has also been shown to be very effective in induction of therapeutic abortion, especially during the 2nd trimester, either by intravenous or therapeutic abortion, especially during the 2nd trimester, either by intravenous or by intrauterine administration. This last way of administration requires a lower dose of the drug; in both modes of administration side effects of vomiting, nausea, and diarrhea are common. The clinical applications of PGs have not yet been completely explored.