Title: The antiprogestins: a recent advance in fertility regulation.

POPLINE Document Number: 050881

Author(s):

Ulmann A

Source citation:

JOURNAL OF STEROID BIOCHEMISTRY, 1987;27(4-6):1009-12.

Abstract:

Ru 486 (mifepristone) is the 1st antiprogestin available for clinical purposes. Its pharmacological properties are presented. It possesses antiprogestin and antiglucocorticoid activities. It is now in phase II- III clinical studies as a fertility control agent. The drug appears useful per se in 4 situations: for early pregnancy (amenorrhea of less than 5 weeks' duration), for late occasional luteal contraception when given as a single dose on the date of the expected period in women at risk for a pregnancy, for dead fetus expulsion in the 2nd or 3rd trimester of pregnancy, and for cervical ripening before such obstetrical procedures in pregnant women as vacuum aspiration or D and C. During early pregnancy, complete interruption is obtained in approximately 90% of the women participating with a single dose of 600 mg. For this stage of pregnancy, RU 486 appears to be an interesting alternative to vacuum aspiration. The antiglucocorticoid activity of the molecule can be demonstrated in humans by a rise in plasma cortisol, ACTH, and LPH after RU 486 intake, and by blockade of some peripheral effects of cortisol. Results obtained in more than 1000 women undergoing shortterm treatment with RU 486 (600 or 800 mg once) clearly indicate that the antiglucocorticoid activity of the molecule has no clinical relevance at the doses used for fertility control purposes. In conclusion, RU 486 appears to be a promising new tool for fertility control, but largescale trials are necessary to confirm for each indication. (author's)

Keywords:

Contraception Research
Female Contraception
Hormone Receptors
Progesterone
Hormone Antagonists
Evaluation
Side Effects
Contraception
Family Planning
Membrane Proteins
Physiology
Biology
Progestational Hormones
Hormones
Endocrine System
Treatment