Clomid Challenge Test

One way to evaluate levels of female hormones for purposes of measuring a woman's fertility is the Clomid challenge test. The test makes use of the well-known fertility drug Clomid (clomiphene citrate) to better determine whether a woman has declining ovarian reserves.

Ovarian reserve is the medical term used to indicate a woman's chances of becoming pregnant. Therefore, a woman with decreased ovarian reserves would be thought of as having below normal chances of conceiving. This test is known by many names: the clomiphene citrate challenge, the clomiphene challenge test, Clomid challenge, or just plain old CCCT.

The focus of the Clomid challenge test is on the hormone known as FSH (follicle stimulating hormone). This hormone serves to stimulate a woman's ovaries so they will develop the egg-containing follicles. When a woman takes Clomid, a small increase in her levels of FSH will be seen. It is this increase of FSH that is hoped will lead a woman to conceive.

Suppressing Hormones

On the other hand, the increased production of FSH stimulates the ovaries to produce something called suppressing hormones, which causes the FSH levels to decline. By the tenth day of the Clomid challenge test, the FSH levels should have been knocked down to normal range because of the effect of the suppressing hormones. If the levels of FSH remain high on the tenth day, this is an abnormal finding and is considered an indication of a poor ovarian reserve.  

It may help to hear an example of how this works. Let's say a 25 year-old woman has had an abnormal result on her Clomid challenge test. That means she is considered as having fewer eggs left in her ovaries. This calculation makes sense because at her age, she would have been expected to still have a lot of eggs left.

Egg Degeneration

On the other hand, a woman who is past menopause would be expected to have these high FSH levels, since it is known that she is no longer fertile. A woman's store of eggs is depleted over time, and can be attributed to a constant state of degeneration. But in some women this rate of degeneration has been accelerated for unknown reasons.

Why perform the Clomid challenge test? The doctor wants to know whether a depleted store of eggs or an accelerated pace for the degeneration of a woman's eggs is a factor in causing a woman's infertility. This can help determine an appropriate, individualized course of fertility treatment.

There are factors other than age or an accelerated pace of degeneration that can lead to depleted stores of eggs including smoking—which is known to cause an abnormal Clomid challenge test result—and surgery on the ovaries which may reduce a woman's store of eggs.