850TO STUDY THE INCLINATION OF SERUM BETA-HUMAN CHORIONIC GONADOTROPIN LEVELS AFTER MEDICAL ABORTION IN THE EARLY FIRST TRIMESTER OF PREGNANCY IN TAMILNADUHuman chorionic gonadotropin (hCG) is produced by the placental trophoblast of normal pregnancy, which is going to have a series of actions in the survival of the embryo and it also maintains progesterone secretion by the corpus luteum. This study is aimed to study the inclination of serum beta-human chorionic gonadotropin levels after medical abortion in the early first trimester of pregnancy. This is a retrospective study of women with early intrauterine pregnancies who underwent medical abortion with mifepristone & misoprostol and had Serum beta-human chorionic gonadotropin levels monitored premifepristone administration (day 1); 48?h post-mifepristone, pre-misoprostol administration (day 3); and anywhere between day 4 to day 10. The percentage of hCG decline in relation to each patient's Day 1 hCG were 59.7% on Day 4, 64.46% on Day 5, 73.62% on Day 6, 88.83% on Day 7, 96.45% on Day 8, 98.71% on Day9 and 99.51% on Day 10. Day 3 hCG values showed a mild increase of 1.5% in relation to Day 1 values. One patient had an up-trending hCG values on Day 3 and Day 5 and on USG had an ongoing pregnancy which was terminated by surgical method. The decline in hCG within the first few days following medical abortion is rapid and predictable as early as Day 4. A decline of 90% and above on days 7-10 can be considered as successful medical abortion. This result is independent of the absolute values of hCG on Day 1 and also independent of the gestational age of the pregnancy.drindu2k@gmail.comResearch7122016 Serial hCG Measurements,Early Pregnancy,Medical Abortion,Follow up, Beneficial EffectsIndu Arun Bhargavi O,SuhasiniAssistant Professor of Obstetrics and Gynaecology, Sri Muthukumaran Medical College Hospital and research institute, Chikkarayapuram, Near Mangadu, Chennai - 600 069, India,Assistant Professor of Obstetrics and Gynaecology , Sri Muthukumaran Medical College Hospital and research institute, Chikkarayapuram, Near Mangadu, Chennai - 600 069, India