question_answer 18)

  Emergency contraceptives are effective if used within 72 hrs of (a) coitus                             (b) ovulation                                      (c) menstruation              (d) implantation

Answer:

                (a)Administration of higher dosesprogestogens or progestogen-estrogen combinations within 72 hrs of coitus have been found to be very effective as emergency contraceptives as they could be used to avoid possible pregnancy due to rape or casual unprotected intercourse. These drugs delay/disrupt the ovulation and fertilization.