It would be fabulous if there were an easy way to count the remaining eggs in your ovary, in much the same way that you could open a carton of eggs from the refrigerator and count how many good ones remain. Alas, there isn’t, but there are several tests that, along with your age, offer the best tools currently available to estimate your remaining pool of viable eggs.
Unfortunately, none of the tests is ideal, and there is no consensus among physicians as to which are the best. However, there is general agreement that a woman’s increasing age will affect the quality of her eggs, and that she should have at least two or three different tests done to get a better indication of the number of viable eggs remaining.
The list of tests below is in approximate order of most predictive:
Antral Follicle Count
This is one of the few exams in which a radiologist can actually pinpoint how many immature resting (antral) follicles are available to develop in that specific cycle. The higher the number observed in the first few days of a cycle, the better the prospects for in vitro fertilization (more than 10 is good, while fewer than five is problematic).
Antimullerian Hormone (AMH) Test
This blood test analyzes levels of the antimullerian hormone, a substance secreted by the cells of the immature follicles. It can be performed at any time during the cycle, but, as with the FSH test below, clinics should use age-specific parameters to get an accurate reading.
Follicle Stimulating Hormone (FSH) Levels
This is the most commonly administered test, though its results are somewhat counterintuitive. It is usually done on Day 3 of the cycle, and the higher the number, the more problematic it is for a woman desiring pregnancy. This is because a higher level means that her body is working harder and harder, releasing excessive FSH just to get the remaining follicles to mature. However, it’s also worth noting that while a high level of FSH may indicate a poor ovarian reserve, a normal level of FHS still doesn’t tell us anything about the quality of the remaining eggs.
Clomiphene Citrate (Clomid) Challenge Test
The purpose of a Clomid challenge test is to determine how efficiently the ovaries are working. A healthy ovary requires only a small amount of FSH to stimulate the follicles to mature an egg. Ovaries that are not functioning optimally, on the other hand, require substantially higher levels. Thus, having elevated levels is considered an indicator of poor ovarian function, though having normal levels does not necessarily guarantee normal ovarian function. Such is life . . . sigh.