Effectiveness of Pretreatment Letrozole Versus Misoprostol Alone in Missed Abortion

Background and Rationale Abortion accounts for about 8% of maternal mortality worldwide. Surgical intervention is the definitive treatment for abortion but it is invasive. Misoprostol, a PG E1 analogue, is exten¬sively used for induction of abortion with success rate less than 90%. Estrogen is important in the maintenance of pregnancy \& aromatase enzyme is essential for its production. Letrozole is an aromatase inhibitor. So we assume that suppression of serum estradiol by letrozole will facilitate termination of pregnancy. Objectives : To compare the effect of a combination of letrozole with misoprostol versus misoprostol alone in successful induction of medical abortion. Study population \& Sample size 150 women will be recruited. Women included will be \> 18 years with singleton pregnancy of gestational age ≤ 20 weeks having missed abortion. They will be excluded if they have prior CS, twin pregnancy, allergy to letrozole or liver problems. Study Design : A randomized controlled trial in which patients will be divided into 2 groups; case group \& control group. Each group will contain 75 patients. Methods : Case group will receive pretreatment letrozole 12.5 mg for 2 days while control group will receive only misoprostol. Both groups will receive misoprostol in a dosage according to the ACOG guidelines based on gestational age. Possible Risk (s) to study population : Major risks (Sepsis, considerable vaginal bleeding leading to hemodynamic instability or necessitating blood transfusion). Minor risks (Nausea, diarrhea, headache, weakness, hot flushes). Outcome parameter (s): Successful medical abortion i.e. complete abortion with no need for surgical curettage within one week from the 1st dose of misoprostol.