On stoppage of the combined estrogen-progestin contraceptive pill, fertility returns after:

Correct Answer: A

Rationale: The correct answer is A (1-2 months) because fertility typically returns quickly after stopping the combined estrogen-progestin contraceptive pill. Estrogen and progestin hormones are quickly metabolized and cleared from the body, allowing the menstrual cycle to resume within a month or two. Choice B (4-6 months) is incorrect as fertility usually returns sooner. Choice C (6-12 months) is also incorrect as it is an extended timeframe for fertility to return. Choice D (Uncertain period) is incorrect as there is a general understanding of the timeline for fertility to return after stopping the pill.

Correct Answer: C

Rationale: The correct answer is C because progestin and estrogen work together to suppress ovulation by inhibiting the release of gonadotropins. Progestin thickens cervical mucus, making it hostile to sperm, while estrogen stabilizes the endometrium. Choices A and B are incorrect because the hormones don't block each other's side effects. Choice D is incorrect because it oversimplifies the mechanism of action.

Correct Answer: D

Rationale: Step-by-step rationale for choice D being correct: 1. Oral mifepristone is a progesterone receptor antagonist, leading to detachment of the pregnancy. 2. Oral misoprostol, a prostaglandin, causes uterine contractions and expulsion of the products of conception. 3. This regimen is safe, effective, and widely used for early pregnancy termination. 4. Choice A, B, and C involve different medications and routes not typically used for nonsurgical termination of early pregnancy.

Correct Answer: C

Rationale: Step-by-step rationale: 1. Mifepristone is an antiprogestin as it competitively inhibits progesterone receptors. 2. Gemeprost is a prostaglandin analog, not an antiprogestin. 3. Megestrol is a progestin, promoting progesterone-like effects. 4. Tamoxifen is a selective estrogen receptor modulator, not an antiprogestin. Summary: A, B, and D are incorrect as they do not possess antiprogestin properties. Mifepristone is the correct choice due to its specific mechanism of action as an antiprogestin.

Correct Answer: A

Rationale: The correct answer is A: Rise in body temperature. Progesterone does not directly cause a rise in body temperature; this is primarily regulated by the hypothalamus. Progesterone's main actions include endometrial proliferation, proliferation of acini in the mammary gland, and suppression of cell-mediated immunity. Endometrial proliferation prepares the uterus for implantation, mammary gland proliferation prepares for lactation, and suppression of immunity prevents rejection of the fetus during pregnancy. Other choices are incorrect because they are well-documented actions of progesterone.