Question

Assertion (A): Ovulation generally will not immediately occur following parturition.
Reason (R): Use of oral contraceptive pills inhibits ovulation.

• A. Both (A) and (R) are true. (R) is correct explanation for (A)
• B. Both (A) and (R) are true. (R) is not correct explanation for (A)
• C. (A) is true. But (R) is false
• D. (A) is false. But (R) is true

Hint:

Lactational amenorrhea is a natural contraceptive method.
It works because high prolactin levels block GnRH secretion, which is entirely different from the synthetic hormone feedback of oral contraceptive pills.

Answer 1

The Correct Option is B

Step 1: Understanding the Question:
This is an assertion-reason question analyzing the temporary suppression of ovulation post-childbirth and the physiological mechanism of oral contraceptives.

Step 2: Key Concept and Approach:
We need to determine if both statements are independently correct, and then check if the inhibition of ovulation by contraceptive pills is the biological reason why ovulation is absent directly after childbirth.

Step 3: Detailed Explanation:

• Post-Parturition Ovulation Suppression: Assertion (A) is true.
Following childbirth (parturition), a mother undergoes intense lactation.
High levels of prolactin during lactation inhibit the release of Gonadotropin-Releasing Hormone (GnRH) from the hypothalamus, preventing the LH and FSH secretion needed for ovulation (lactational amenorrhea).

• Oral Contraceptive Action: Reason (R) is true.
Oral contraceptive pills typically contain combinations of synthetic progesterone and estrogen.
These hormones provide negative feedback to the pituitary gland, preventing the LH surge and thereby inhibiting ovulation.

• Causal Link Analysis: Although both statements are correct scientific facts, the reason why ovulation does not occur post-parturition is due to endogenous lactational prolactin, not due to the intake of oral contraceptive pills.
Therefore, Reason (R) is not the correct explanation for Assertion (A).


Step 4: Final Answer:
Both (A) and (R) are true, but (R) is not the correct explanation for (A).