Abstract

PIP: Different types of prostaglandins (PG) have various effects on tissue in different functional states. Their complex effects include uterine contractions, expansion or contraction of blood vessels, and promotion or prevention of platelet aggregation. The large body of work done on the role of PG in the effects and side effects produced by IUDs is reviewed. PG concentrations in the human endometrium during the menstrual cycle vary according to PG type and menstrual phase. Evidence is cited showing that overall PG levels or levels of certain types of PG rise with IUD, and that this is a local reaction. In 1976 non-steroidal anti-inflammatory drugs were successfully used to reduce uterine bleeding. The means by which the IUD induces abnormal uterine bleeding has not been determined. Some authors have sought to explain the rise in PG by means of aseptic inflammation of the endometrium. The possible role of platelets, thrombus, and expansion and contraction of blood vessels in bleeding with IUD has been raised. The uterus with IUD becomes more active. When IUD is designed too large or insufficiently pliable, abnormal bleeding may occur in menstruation. The presence of an IUD makes the uterus highly sensitive to PG, so that even normal PG levels can cause a strong reaction in the uterine smooth muscle. PG plays an important role in the mechanisms of abnormal uterine bleeding; PG suppressants will be significant in treating abnormal uterine bleeding with IUD.