Ovarian Reserve Assessing Ovarian Function
Assessing ovarian function relates to “How well are the ovaries and eggs inside working?” Women are born with a lifetime’s supply of eggs and each month an egg(s), contained within the ovarian follicle, is stimulated to grow and develop by the hormone FSH. When a woman is ovulating monthly, she generally releases one egg each month.
The hormone FSH is one of the tests that can be used to assess egg number (ovarian reserve). As the woman ages there is an accompanying increase in FSH levels. Aging has a strong effect on both egg numbers and the ability of the egg to give rise to a normal pregnancy.
FSH is usually measured on day three of the menstrual cycle and abnormally high levels predict a poor prognosis for fertility treatments. Sometimes our fertility specialists will order the Clomid Challenge Test to more thoroughly evaluate ovarian reserve. Cut offs for FSH levels at certain times of the cycle have to be extensively researched and offer predictive value with how well ovaries are functioning and the chances of response to infertility treatment.
The Clomid Challenge Test provides an indication of how the woman with an elevated FSH level will respond to ovarian stimulation by FSH (Follistim, Gonal-F, Bravelle, Repronex, and Menopur) fertility drugs. The Clomid Challenge Test is conducted as follows:
Day 3 FSH and estradiol levels are measured and 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.
Another test to gain information about ovarian reserve is anti-mullerian hormone (AMH) level in the woman’s blood. This blood test can be done on any day of the menstrual cycle. An abnormally low AMH hormone indicates a decreased reserve of eggs, in the same way that an elevated FSH level indicates decreased reserve.
A poor Clomid Challenge Test, a high day 3 FSH, or a low AMH often indicates that there will be a decreased response to ovarian stimulation, pregnancy success rates will be lower, and that there may be an increased chance of miscarriage. In younger women (<35 years old) the elevations in FSH are often indicative of waning ovarian function but options such as IVF are often still successful.)
In women over 35 and certainly over 40 years old, an elevated FSH or abnormal CCCT or AMH indicates chances for successful pregnancy are often 5-10%. In that circumstance, many couples will choose donor egg IVF instead because of its high success rates.