Termination Of Anembryonic Pregnancy

Overview

Anembryonic pregnancy is a leading cause of early miscarriage. The American Pregnancy Association estimates that blighted ovum causes approximately 50 percent of all first-trimester miscarriages. About 20 percent of all pregnancies result in miscarriage. In general, there are 3 options for management of anembryonic pregnancy: expectant, medical, and surgical management. Expectant management consists of no intervention and awaiting natural passage of tissue. Medical management uses medication to expel uterine tissue. Surgical management is defined by mechanical removal of tissue from the uterus. Medical management allows patients to avoid surgery and anesthesia. Patients may also feel that medical management is more private, and under their control. Several medications have been studied for medical management. Misoprostol, a prostaglandin E1 analogue, is a uterotonic that results in cervical softening and contractions that expel the products of conception. It may be administered vaginally, orally, buccally, or sublingually. Adverse effects vary based on route of administration. There is published literature on a wide range of therapeutic misoprostol regimens. Optimal dose and route of administration of misoprostol have not been determined by randomized trials. Overall, misoprostol is safe and well-tolerated. Patients receiving misoprostol vaginally rather than orally have decreased adverse gastrointestinal effects and prolonged duration of action. Oral misoprostol is less effective than vaginal misoprostol in emptying the uterus. Sublingual misoprostol is equivalent to vaginal misoprostol in inducing complete uterine emptying but is associated with more frequent diarrhea. When compared with lower dosages, a dose of 800 µg vaginal misoprostol is more effective at completing uterine emptying, although it results in a similar incidence of nausea. Based on international trials in settings with limited resources, WHO recommends a single vaginal dose of 800 µg misoprostol for medical management of anembryonic pregnancy. Routes of misoprostol administration include oral, vaginal, buccal or rectal. Vaginal misoprostol is associated with a greater overall exposure to the drug and greater effects on the cervix and uterus. Isosorbide mononitrate (IMN) is a drug used principally in the treatment of angina pectoris, which acts by dilating the blood vessels so as to reduce blood pressure.