Your ovarian reserve is a term that refers to both the quantity and quality of eggs you have left. It only refers to your fertility potential. It does not include any problems in your reproductive tract—fallopian tubes, uterus, or vagina. It also depends on how well your egg follicles respond to hormone signals given from the brain.
Your egg cell—known as the oocyte or ovum—is the female sex cell, or gamete. This large, round cell develops in one of your two ovaries. When ovulation occurs, the mature egg is released from the ovary, where it travels into the fallopian tubes so it can be fertilized by sperm. If fertilization does occur, it can become an embryo and attach to your uterine lining, developing into a healthy pregnancy.
So why are egg quantity and quality so important? Both of these are vital indicators of your ability to get pregnant. Egg quantity is straightforward. When you are born, you already have a certain number of eggs in your ovaries. As you age, the number declines. And the fewer eggs that you have, the more difficult it is for your body to recruit and develop an egg. Ovulation is necessary for pregnancy, and it can be difficult to conceive if your ovulation is irregular.
Egg quality is a little more complex. Some women believe that menstruating regularly is a surefire indication that their eggs are just fine. However, even if you ovulate, it doesn’t necessarily mean the eggs are of a higher enough quality to result in a pregnancy. For instance, if an egg of poor quality is fertilized, it may be unable to implant, it may result in a miscarriage if it cannot develop correctly, or a baby born with birth defects.
While poorer-quality eggs is often associated with older women, it’s important to note that younger women can have lower-quality eggs as well. That may be because of smoking, radiation, chemotherapy, endometriosis, or even genetics.
Before you freeze your eggs, there are a few required tests that measure your ovarian reserve. These may include the Day 3 follicle stimulating hormone (FSH) levels test, Estradiol levels test, Clomiphene challenge test, and Anti-Mullerian Hormone (AMH) levels test. You may also undergo an ultrasound for an antral follicle count test.
Testing your ovarian reserve before egg freezing is important because it helps your fertility doctor determine which ovarian stimulation treatment would be most effective in producing—and then retrieving—the greatest number of eggs possible.