Clomid Challenge Test
The Clomid challenge test (CCCT) provides an indication of how the patient will respond to ovulation induction with FSH for an IVF cycle and is usually the best predictor of ovarian reserve. A significantly elevated FSH level on day 3 suggests a poor prognosis for pregnancy success. There are many fertility programs that will not allow a patient who has an abnormal CCCT undergo IVF treatment.
The CCCT is performed by measuring the day 3 FSH and estradiol levels, the patient takes 100 mg. of Clomid on cycle days 5-9, and her FSH is measured again on day 10. The test is abnormal if either the day 3 or day 10 FSH values are elevated (above 12) or if the day 3 estradiol is greater than 65 pg/ml. Marginal values for FSH are between 10 and 12. The prognosis is less predictable with marginal values but most patients will require high doses of FSH for adequate stimulation during an IUI or IVF cycle.
An abnormal Clomid challenge test, regardless of the patient's age, indicates that there will be a decreased response to injectable FSH, that pregnancy success rates will be low, that there may be an increased chance of miscarriage and that there may be an increased chance for chromosomal abnormalities in an ongoing pregnancy.
Patients with poor Clomid challenge test results are encouraged to consider our donor egg program where success rates are much higher. After appropriate discussions, patients with a poor CCCT result are not usually barred from attempting IVF unless the FSH level is above 20. However, we emphasize that the pregnancy prognosis is usually poor (5% delivered pregnancy rate or less).