Which of the following is true regarding RU 486?
A. Prevents fertilization
B. Has affinity for estrogen receptors
C. Single dose of 10mg prevents pregnancy in 90% cases
D. Causes delayed menstruation
Correct answer : D. Causes delayed menstruation
- RU 486 (mifepristone) does not prevent fertilization.
- It has affinity for progesterone receptors.
- It blocks the action of progesterone on the endometrium.
- It prevents implantation by causing sloughing and shedding of decidua.
- Single dose of 10mg prevents pregnancy in 99.1% cases.
Ref: Shaw’s Textbook of Gynaecology, 15th edition, p237.