A couple is undergoing evaluation for difficulty conceiving a child. The female is able to ovulate, and the male produces adequate normal sperm. The woman reports 20 days between menses. What problem does this suggest? Her pituitary does not produce follicle-stimulating hormone. The corpus luteum may cease production of progesterone too soon. O Her pituitary does not produce luteinizing hormone. Her hypothalamus does not produce gonadotropin-releasing hormone.

The corpus luteum may cease production of progesterone too soon.

Explanation:

The couple is undergoing evaluation for the conceiving the baby. The only problem is that the women reports the 20 days in between the menses which is unusual.

The cycle should be of 28 days plus minus 2 days. The reason could be ceasing of the corpus luteum which stops the production of progesterone too soon which makes the cycle abnormal.

Progesterone prepares the body for pregnancy after ovulation. It thickens the wall of endometrium in order to make the body ready for pregnancy.

If there is ceasing of progesterone to early then the body will start ovulating too early and the body will not conceive  

Progesterone prepares the endometrium for the potential of pregnancy after ovulation. It triggers ovulation and there is only a gap of 20 days in between two cycle.

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