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Question #45533
The Question
A woman relying on lactational amenorrhea as a contraceptive method reduces her breastfeeding frequency at 4 months postpartum. She conceives despite not having experienced her first postpartum menses. Which of the following statements accurately describes the physiological basis for this contraceptive failure?
Options
- A.
Decreased suckling frequency leads to a rapid decline in oxytocin, which removes the negative feedback on the anterior pituitary, restoring FSH and LH pulses.
- B.
The drop in prolactin levels removes its inhibitory effect on the pulsatile release of GnRH from the hypothalamus, allowing an LH surge and ovulation prior to endometrial shedding.
- C.
Reduced prolactin directly upregulates FSH receptors on the ovarian granulosa cells, initiating follicular development independent of the hypothalamus.
- D.
Decreased suckling reduces dopamine release from the hypothalamus, which directly triggers the adenohypophysis to resume the menstrual cycle.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Regulatory_Failure
Understand how NOT, EXCEPT, and logical constraints are used to manipulate exam results.
Concepts Behind This Question
Secondary Messenger Cascade|Prolactin|GnRH_Receptors
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Distinguishing the specific roles of Prolactin vs.
Oxytocin, and understanding the kinetic sequence of the menstrual cycle where ovulation strictly precedes menstruation.
Common Misconception: Students often assume menses must return before a woman becomes fertile again, and frequently confuse the milk-ejection reflex (Oxytocin) with the milk-synthesis/contraceptive reflex (Prolactin).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Reproductive Health - Class 12 |
| Concept | Lactational Amenorrhea Logic |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |