Antiprogesterone compound RU-486 is effective for inducing aboion if the duration of pregnancy is :

Ans. is a i.e. 63 days RU-486 i.e. Mifepristone, is an analogue of the progestin "norethindrone". which has strong affinity for progesterone receptors but acts as an antagonist of progesterone. Given alone, the drug was moderately useful in causing aboion of early pregnancy, however the combination of mifepristone with analogue of prostaglandin E, i.e. misoprostol is very effective. hegimen : FDA approved protocol - (Original protocol) : 600 mg of Mifepristone (i.e. 3 tablets) given orally on day 1 followed 2 days later by oral misoprostol 400 pg (2 tablets) on day 3. The treatment should be staed no more than 49 days from the sta of the last menstrual period. But according to the recent protocol : 200 mg of mifepristone (it is as effective as 600 mg of mifepristone) is given orally on Day 1 followed 2 days later by vaginal misoprostol 800 pg. ibis regime provides highest efficacy within 63 bays of amenorrhea. Role of mifepristone in Medical aboion : Mifepristone blocks progesterone receptors in the endometrium which leads to disruption of the embryo. production of prostaglandins and a decrease in human chorionic gonadotropin levels. The success rate is dependant on the length of pregnancydeg - the more dependant the pregnancy is on progesterone from the corpus luteum, the more likely that the progesterone antagonist, mifepristone will result in aboion. The production of prostaglandins leads to softening of the cervix as well. Also Know : Contraindications of Medical aboion with mifepristone / misoprostol : ectopic pregnancydeg an IUCD in placedeg chronic adrenal failuredeg concurrent long term coicosteroiddeg therapy history of allergy to mifepristone, misoprostol or other prostaglandinsdeg inherited porphyrias Severe anemia, coagulopathy or anticoagulant use. - Active liver disease Uncontrolled seizure disorder. - Cardiovascular disorder. Relative Contraindication--renal disease