Every woman is born with all of the eggs that she will ever have in her lifetime. When a woman goes through puberty, her ovary becomes active, functioning as a virtual “egg bank” that delivers eggs once a month until the woman reaches the age of menopause. Ovarian reserve testing is a special test that can give women vital information about the number of eggs remaining and their fertility.
What is Ovarian Reserve Testing?
Most women undergo ovarian reserve testing as part of fertility treatment. Ovarian reserve testing is also required for women who want to undergo IVF (in vitro fertilization). During the test, her eggs, referred to medically as “oocytes”, are both counted as well as examined for various markers that help determine fertility.
Most ovarian reserve testing is done indirectly. Instead of using invasive techniques to enter the ovaries and physically count the number of oocytes, doctors use a variety of techniques to measure
estrogen and other hormone levels to determine both the number and viability of a woman’s eggs.
How Does Ovarian Reserve Testing Work?
There are a number of indirect methods to test the viability and estimate the number of eggs that a woman has remaining.
The Day 3 FSH Test
The most common test is known as the Day 3 FSH Test. On the third day of a woman’s menstrual cycle, a blood sample is taken and analyzed for the level of FSH (follicle stimulating hormone). Day 3 of the menstrual cycle is considered ideal because estrogen levels are naturally low, making it easier to detect FSH levels.
By analyzing FSH levels, doctors can get a better understanding of a woman’s fertility. If FSH levels are low, women have a better chance of fertility while higher levels indicate that there may be
difficulties in conceiving. FSH is an important hormone that regulates how follicles in the ovary either become viable eggs or self-terminate in the natural process of menstruation.
The FSH test usually also measures the levels of estradiol in the bloodstream, which works to suppress FSH. If repeated tests show that FSH levels are within normal levels but there is a high level of estradiol, it is believed that the estradiol is working against the FSH in order to produce viable eggs.
The Day 3 FSH Test is the most common ovarian reserve test used today
but two other tests have become more popular due to disagreement about
how to precisely match FSH levels with to a woman’s ability to
successfully conceive. Sometimes, doctors will also use a Day 10 FSH
test to better monitor the levels of FSH and estradiol throughout the
course of a woman’s menstrual cycle.
Inhibin B Test
Inhibins are special proteins produced in the ovaries. The beta or B variant of inhibin works against the FSH hormone. By measuring the levels of Inhibin B in the blood, doctors can detect certain forms of ovarian tumors and other problems with the ovaries, as well as help understand the viability of a woman’s eggs. A high level of Inhibin B means there are more viable potential eggs present.
The Inhibin B test is usually conducted on day three of the menstrual cycle in conjunction with the FSH test.
CCCT
Commonly referred to by its initials, the Chlomiphene Citrate Challenge Test was originally developed as an improvement to the 3 Day FSH test for women who were 35 or older.
In addition to the Day 3 FSH and Day 10 FSH test, the CCCT involves consuming 100 milligrams of clomiphene citrate on days five through nine of the menstrual cycle. If FSH levels go up, this can be
an indication that there are ongoing fertility problems. If the clomiphene citrate successfully works to repress FSH levels, this is considered a positive indication of fertility. The CCCT is often used
because it is easier to measure clomiphene citrate levels than FSH in the bloodstream.
AMH Test
The Anti-Mullerian Hormone or AMH test measures a special protein that is produced by follicles in the ovaries. It is believed that the AMH hormone works to minimize the effects of FSH and thus higher levels of AMH are thought to indicate an increased ability to successfully
conceive.
Ultrasound
Similar to ultrasound tests used for pregnant women, sound waves are directed towards the ovary in an effort to measure the volume of a woman’s ovary. A bigger ovary size with a higher number of follicles indicates a higher level of fertility.
Age and Testing the Fertility of Eggs
All of the above tests are useful for determining egg quality, but the most significant factor in female fertility is the age of the woman. As a woman ages, changes in the chromosomes lead to an increased risk of producing infertile eggs. Most studies show that a woman’s eggs are at peak fertility between the ages of 21 to 35, with a steady decline as a woman reaches age 50.
Ovarian reserve testing is especially useful for women over the age of 35 and anyone experiencing difficulty in conceiving.
Limitations of Ovarian Reserve Testing
It cannot be emphasized strongly enough that all of the blood analysis tests used to determine ovarian reserve are subject to interpretation. Furthermore, hormone and protein levels fluctuate quite dramatically throughout the menstrual cycle, and it can often be difficult to
obtain a very precise reading.
Results indicating a low chance of a successful pregnancy do not rule out any chance of conceiving. It can be quite emotionally traumatic to receive official-sounding results that indicate that a pregnancy is impossible. One should always keep in mind that fertility science is still in its infancy and no individual result can ever say with complete certainty whether or not a successful conception is possible.