The clomiphene challenge test may be used to check egg supply (ovarian reserve). But this test is not done often because there are other tests that work better for checking egg supply.

The clomiphene challenge test is done over many days. Clomiphene is a fertility medicine that stimulates the pituitary to release hormones that cause the ovaries to release eggs. A blood test to measure follicle-stimulating hormone (FSH) level is done on days 3 to 5 of her menstrual cycle, followed by 5 days of an oral dose of clomiphene. On day 10, blood FSH levels are measured again. An elevated FSH level on days 3 to 5 or day 10 may mean a low ovarian reserve. A high FSH level can be a sign that the ovaries are having trouble releasing eggs.