The Clomid Challenge Test is a commonly ordered test of ovarian reserve, or egg quality. Women are born with a limited number of eggs, and those eggs decrease in quantity and in quality as women age. A patient’s ability to become pregnant depends, in large part, upon the remaining number and quality of her eggs. The Clomid Challenge test is a reflection of a woman’s ovarian reserve, or indirectly, her fertility potential.
During fertility testing it is important to evaluate how far a patient has progressed through the process of depleting her ovarian reserve. While no test is 100% predictive, the Clomid Challenge Test appears optimally suited as a simple, yet accurate, screening tool of ovarian reserve.
A woman’s blood FSH and estradiol levels are analyzed on the third day of her menstrual cycle. Clomiphene citrate (Clomid) tablets at a dosage of 100 mg per day are taken from cycle days 5 through 9. The full dosage (two 50 mg tablets) should be taken at one time, and the medication should be taken at approximately the same time each day. The FSH and estradiol levels are measured again on cycle day 10. Elevated values of FSH, i.e. generally greater than 10 mIU/mL, on either day of testing are usually considered abnormal, and suggest a decline in that patient’s ovarian reserve. The meaning of the estradiol levels are less well understood, although some studies have shown that elevated (> 100 pg/mL) estradiol levels on menstrual cycle day 3 also may reflect a drop in ovarian reserve, especially in reproductively older women (> 35 years).
The Clomid Challenge Test is a provocative test that can identify women with poor ovarian reserve who might not be detected by day 3 FSH screening alone. It has been suggested throughout the medical literature that women with abnormal Clomid Challenge testing should consider more aggressive fertility treatments. This test should especially be considered in patients who:
- Are over 35 years of age
- Have no other obvious cause for their infertility
- Have been trying to conceive without success for greater than 1‐2 years