The number of eggs may be low, or the quality may be poor.
The number and quality of eggs (ovarian reserve) may begin to decrease at age 30 or even earlier. They decrease rapidly after age 40. But age is not the only cause. Abnormalities in the ovaries can also cause such a decrease. The number of eggs in the ovaries decreases early in premature ovarian failure (primary ovarian insufficiency). In a few women, this disorder is the reason they have irregular menstrual periods or no periods.
Diagnosis and Treatment
Doctors may evaluate the following women for problems with eggs:
Doctors can usually confirm the diagnosis by measuring levels of follicle-stimulating hormone (which triggers ovulation) and estrogen in the blood at a certain time during the menstrual cycle. Sometimes doctors give women clomiphene, a fertility drug, before measuring these levels.
Doctors may do blood tests to measure levels of antimüllerian hormone, which is produced by the structures that contain the egg (follicles). A low level of this hormone indicates that the number of follicles is small. Or doctors may use an ultrasound device that is placed in the vagina (transvaginal ultrasonography) to view and count the number of follicles. A small number of follicles means that pregnancy after in vitro fertilization is less likely.
Because pregnancy may be possible, doctors suggest different treatments for each woman based on her circumstances and age. Such treatments include those used to treat problems with ovulation, such as clomiphene, aromatase inhibitors, and human gonadotropins (see Treatment). If women are older than 42 or if the number or quality of eggs is decreased, using eggs from another woman (donor) may be the only way to achieve pregnancy.
Last full review/revision February 2013 by Robert W. Rebar, MD