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Question #45531
The Question
A nursing mother relying on lactational amenorrhea as a contraceptive method begins supplementing her 4-month-old infant's diet with formula milk. She assumes she is completely protected from pregnancy until her first postpartum menstrual bleeding occurs. Which of the following best explains the physiological flaw in her assumption?
Options
- A.
Reduced suckling lowers prolactin levels, removing the inhibition on hypothalamic GnRH secretion, which can lead to ovulation before the first postpartum menstruation.
- B.
The introduction of formula milk directly stimulates the anterior pituitary to release LH, causing ovulation independent of hypothalamic control.
- C.
Decreased prolactin levels stimulate the immediate regression of the corpus luteum, triggering a withdrawal bleed before ovulation can occur.
- D.
Reduced suckling increases oxytocin levels, which synergizes with FSH to promote rapid follicular development and ovulation.
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
Hypothalamic-Pituitary Axis Integration|GnRH|LH_Surge
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often equate 'amenorrhea' (absence of menses) with 'anovulation' (absence of ovulation) as a simultaneous state.
The trap is failing to recognize the chronological sequence of the menstrual cycle: when the HPG axis re-initiates after prolactin inhibition drops, ovulation occurs approximately 14 days BEFORE the first menstrual bleed.
Therefore, waiting for menses as a 'warning sign' of returning fertility is biologically flawed.
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 |