Abstract

PIP: The medical methods of terminating early pregnancy, i.e., prostaglandins, progesterone synthesis inhibitors and progesterone receptor antagonists are reviewed and compared to vacuum aspiration from the research literature. All of these methods have decreasing effectiveness up to the 9th week, when rates of incomplete abortions increase to about 40%. 1 PGF analogue and 3 PGE analogues are available and feasible for clinical use as early abortifacients. Gastrointestinal side effects are universal with the PGF, but only 20-40% with the PGE analogues. Epostane is a progesterone synthesis inhibitor, blocking 3beta-OH-steroid dehydrogenase. RU-486 and ZK 98734 are progesterone receptor antagonists. These drugs cause progesterone withdrawal over a few days, causing detachment of the trophoblast, impaired beta-hCG production, increased sensitivity of the myometrium to PGs and possibly ripening of the cervix. A single 800 mg dose of RU-486 induced complete abortion in 85% of women up to 10 days after the missed period. For routine clinical use RU-486 is taken for 3 days and sulprostone or gemeprost (PG analogs) are given intramuscularly or vaginally, with results comparable to vacuum aspiration. Bleeding lasts longer with the combined medical treatment, averages 62-81 ml, but may be severe enough to require transfusion in 0.15%. About 40% of women had nausea and vomiting. Progesterone and hCG levels declined rapidly after 3 days, and prolactin levels rose. With PGs, cortisol levels rise and the pregnancy hormones fall more rapidly. The antiprogestins decrease glucocorticoid activity but not enough to affect the feedback system. While no psychological studies have been reported comparing the combined medical abortion treatment with vacuum aspiration, prostaglandin treatment was preferred over aspiration. Home treatment with PGs, however, reduced proportion of women needing morphine analgesia from 40 to 5% compared to hospitalization.