estrogen/prog question

[xtra333]

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I got this question from mcat achiever. bad program I know, but I 've already did the aamc exams and need extra materials and second time mcater. anyways

What physiologic event will take place if both estrogen and progesterone levels remain high in the human female blood for a prolonged period of three months?

A)a 28 day menstrual cycle will occur

B)Ovulation will occur

C)Ovulation is unlikely; positive feedback inhibition of LH secretion on anterior pituitary

D)Ovulation is unlikely to occur; negative feedback inhibition of LH secretion of anterior pituitary

I chose C but they answer they gave in the program was D. anyone care to explain why. or is this a bad question?

 

[Hadi7183]

D is right. Those hormones have NEGATIVE feedback (inhibitory) effect on LH secretion.


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[Hadi7183]

Keep in mind that estrogen and progesterone together have negative feedback on LH secretion (what's happening after ovulation), but estrogen alone has positive effect (happening before ovulation).


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[xtra333]

Keep in mind that estrogen and progesterone together have negative feedback on LH secretion (what's happening after ovulation), but estrogen alone has positive effect (happening before ovulation).


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yes I understand that, but the question seems to imply that the event is prior to ovulation. so shouldn't there be a positive effect?

 

[Hadi7183]

Sorry, I don't see how that's implied, but it doesn't matter anyways. What matters is that when you have both estrogen and progesterone, negative feedback on LH happens. The relative timing is not a determining factor in this question.


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[xtra333]

sorry, I made a bad guess. but during the later phases of the menstrual cycle progeston inhibits, but in midcycle progesterone is a positive feedback.

so I had trouble determining which phase (time period ) of mentrual cycle it was