Mifepristone early pregnancy

Ulmann A, Silvestre L, Chemama L, Rezvani Y, Renault M, Aguillaume CJ, Baulieu EE. Medical termination of early pregnancy with mifepristone (RU 486) followed by a prostaglandin analogue. Study in 16,369 women. Acta Obstet Gynecol Scand 1992 71(4) 278-83. 

Maria B, Stampf F, Goepp A, Ulmann A. Termination of early pregnancy by a single dose of mifepristone (RU 486), a progesterone antagonist. Eur J Obstet Gynecol Reprod Biol 1988 28(3) 249-55. 

Hill, N. Eerguson, J. MacKenzie, I. The efficacy of oral mifepristone (RU 38,486) with a prostaglandin El analog vaginal pessary for the termination of early pregnancy complications and patient acceptability. Am. J. Obstet. Gyn. 1990, 162, 414-417. 

In the cervix, progesterone suppresses nitric oxide (NO) production [29]. In contrast, mifepristone stimulates NO release, and the expression of inducible NO synthase in the human cervix in early pregnancy, suggesting that this is the mechanism whereby mifepristone initiates cervical ripening [30]. 

Cheng, L., Kelly, R.W., Thong, K.J., Hume, R. and Baird, D.T. (1993) The effects of mifepristone (RU486) on prostaglandin dehydrogenase in decidual and chorionic tissue in early pregnancy Human Reproduction, 8, 705-709. 

In another study conducted to evaluate different buccal misoprostol doses following mifepristone in women requesting medical termination of early pregnancy (n = 1122), Chong et al. demonstrated that 400 ng of buccal misoprostol taken 36-48h after 200 mg mifepristone is as effective as the standard 800-ng dose in terminating pregnancies up to 63 days last menstrual period and reduced the appearance of side effects [79 ]. 

Creinin MD, Schwartz JL, Pymar HC, Fink W. Efficacy of mifepristone followed on the same day by misoprostol for early termination of pregnancy report of a randomised trial. BJOG 2001 108(5) 469-73. 

Mifepristone and levonorgestrel are also synthetic steroids that contain an alkyne functional group. Mifepristone, also known as RU-486, induces an abortion if taken early in pregnancy. Its name comes from Roussel-Uclaf, the French pharmaceutical company where it was first synthesized, and from an arbitrary lab serial number. Levonorgestrel is an emergency contraceptive pill. It prevents pregnancy if taken within a few days of conception. 

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