At birth, the female ovary has a finite number of oocytes (eggs) available for ovulation during a woman’s reproductive years. Fertility in women starts to decline at about age 27, and drops off more rapidly after age 35. Ovarian reserve refers to the number and quality of eggs available for ovulation at any given age.

While age alone is currently the most reliable indicator of egg number and quality, several tests are available to evaluate the woman’s ability to produce good quality eggs capable of fertilization. Most tests are typically performed on day 3 of the menstrual cycle:

• Follicle Stimulating Hormone (FSH) level – FSH is an important hormone that regulates the recruitment and development of your eggs.  In general, if you are under age 40, a low FSH level is reassuring, and indicates that you probably have good quality eggs. A high level of FSH level suggests that there is a reduction in both the number and quality of eggs remaining in your ovaries (Diminished Ovarian Reserve – DOR). The most reliable indicator of egg quality, however, is your age. So if you are 44 years old and you have a normal FSH level, you can not assume that the quality of your eggs is good. In fact, your chance of conceiving with IVF  is only 2%. Likewise, young women with high FSH may have fewer eggs remaining but their egg quality may still be good yielding satisfactory IVF pregnancy rates. High FSH levels are typically seen in older women, and in women with history of ovarian surgery, chemotherapy, radiation and/or endometriosis. Generally speaking FSH levels below 10miu/ml are reassuring, while FSH levels in the 12-15miu/ml range indicate lower egg quality and poorer IVF success rates. Women with FSH levels over 20miu/ml rarely benefit from treatment utilizing their own eggs and they should be encouraged to consider donor egg IVF  or adoption.
• Estradiol (E2) level – High estrogen level on day 3 of cycle is indicative of Diminished Ovarian Reserve (DOR) even if the FSH level is completely normal. So it is very important to measure both day 3 FSH and estrogen (E2) levels since an elevation in one or both tests may be equally predictive of decreased egg number and lower egg quality. Ideally, day 3 estrogen levels should be less than 50pg/ml.  Day 3 estrogen levels greater than 100pg/ml is considered abnormal.
• Clomiphene Citrate Challenge Test (CCCT) – this test is used to detect poor ovarian reserve in women whose day 3 FSH level is still normal. The test is performed as follows:
  • Day 3 of cycle – blood test to measure FSH and estradiol levels.
  • Clomiphene  (100 mg) is given on days 5-9 of the cycle.
  • FSH level is repeated on day 10 of the cycle.
  The test is considered abnormal if the FSH level on either day 3 or day 10 is greater than 12. The test is also considered abnormal if the day 3 estradiol level is greater than 100. The test has not been universally accepted because the CCCT appears to have no advantage over a simple cycle day 3 FSH level when evaluating the ovarian reserve.
• Antral Follicle Count (AFC) – This is an ultrasound examination performed between days 2-4 of the menstrual cycle to determine the number of antral follicles (immature eggs smaller than 10mm) present within the ovary. Low numbers of antral follicles (less than 4) is suggestive of DOR (Diminished Ovarian Reserve) and may correlate with poorer IVF  outcome.

• Inhibin-B level - This hormone level measured on day 3 of the cycle decreases in women with poor ovarian reserve. Several studies suggested that low day 3 serum inhibin-B may be predictive of a poorer response to ovulation induction as compared with women with a high day 3 inhibin-B. Many centers, however, do not order this test because abnormal values have not been clearly established.
• Antimullerian Hormone (AMH) level – Studies have demonstrated a gradual decrease in AMH levels as a woman gets older. This decline has been attributed to a decreasing number of eggs within the ovary. A low level of AMH suggests that the ovary may be depleted of eggs, and is predictive of low egg production (poor response) during In Vitro Fertilization  (IVF).