Diminished ovarian reserve is a condition where the ovaries have fewer eggs compared to others of the same age. This lower egg count can make achieving pregnancy more challenging. The term refers to the number of eggs, not necessarily their quality, though the two factors can be related.
What Causes Diminished Ovarian Reserve?
The most common cause is the natural aging process. Women are born with all the eggs they will ever have, and this number steadily decreases over their lifetime. This decline often accelerates after age 35, leading to a smaller pool of available eggs. In some individuals, this process happens earlier or more rapidly than expected for their age group.
Genetic factors can also cause diminished ovarian reserve. Certain abnormalities involving the X chromosome, such as Fragile X syndrome, are linked to a lower egg count. A family history of early menopause may also suggest a genetic predisposition to a faster decline in ovarian reserve.
A person’s medical history can contribute to a reduced egg supply. Surgeries on the ovaries, for instance to remove cysts or treat endometriosis, can inadvertently remove healthy ovarian tissue. Conditions like endometriosis itself can damage the ovaries. Autoimmune diseases are another potential cause, as the body’s immune system may mistakenly harm ovarian tissue.
Certain medical treatments are a documented cause. Chemotherapy and radiation therapy, particularly when directed at the pelvis for cancer treatment, can be toxic to the ovaries and destroy a portion of the egg supply. The extent of the damage often depends on the type of treatment, the dosage, and the person’s age. Smoking is a lifestyle factor associated with accelerating the loss of ovarian reserve.
Diagnosing Diminished Ovarian Reserve
Most individuals with diminished ovarian reserve do not experience any obvious signs. Often, the first indication is difficulty becoming pregnant. As the condition progresses, some may notice a shortening of their menstrual cycle length; for example, a cycle that was once 28 days may become consistently 24 days. Only when menopause is approaching might more noticeable signs like hot flashes or missed periods appear.
To diagnose the condition, healthcare providers rely on a combination of blood tests and imaging. One of the primary blood tests measures Anti-Müllerian Hormone (AMH). AMH is produced by follicles in the ovaries, so a lower AMH level suggests a smaller egg supply. This test can be performed at any point in the menstrual cycle.
Another test measures Follicle-Stimulating Hormone (FSH). When the number of available follicles is low, the brain releases more FSH to try to stimulate the ovaries. A high FSH level, measured early in the menstrual cycle, can indicate diminished ovarian reserve.
A transvaginal ultrasound is also used to perform an antral follicle count (AFC). This imaging test allows a provider to visually count the resting follicles in the ovaries at the beginning of a menstrual cycle. A low count corresponds with a lower overall ovarian reserve.
How Diminished Ovarian Reserve Affects Fertility
Diminished ovarian reserve primarily impacts fertility by reducing the number of available eggs for fertilization. With a smaller pool of eggs, the chances of a healthy, viable egg being released and successfully fertilized in any given month are lower.
Advancing age, a primary cause of lower egg quantity, is also linked to a decline in egg quality. As eggs age, they are more prone to containing chromosomal abnormalities. These genetic issues can prevent an embryo from developing properly, leading to implantation failure or early miscarriage.
This combination of fewer eggs and potentially lower-quality eggs also affects fertility treatment outcomes. During treatments like in vitro fertilization (IVF), the goal is to stimulate the ovaries to produce multiple mature eggs. Patients with a lower reserve may not respond well to stimulation medications, resulting in fewer eggs retrieved and fewer embryos to work with.
Fertility Treatment and Management Options
Several medical interventions can help manage the challenges of diminished ovarian reserve. In Vitro Fertilization (IVF) is a common approach, as it aims to maximize the potential of the remaining eggs. Specialists may adjust IVF protocols, using different medication strategies to optimize the ovarian response.
Using donor eggs is a highly effective alternative when a person’s own eggs present a barrier to pregnancy. This process involves using eggs from a screened donor, which are then fertilized with sperm. The resulting embryo is transferred to the recipient’s uterus. This option consistently yields high success rates for individuals with this condition.
Certain lifestyle choices can support reproductive health, though they cannot reverse a low egg count. Avoiding smoking is important, as tobacco use is linked to accelerated ovarian aging. Maintaining a healthy weight and managing stress are also beneficial.
Fertility preservation, or egg freezing, is another strategy. This involves retrieving and cryopreserving eggs for future use. This is an option for those who are aware of their declining reserve and wish to preserve their current egg quality for a later time.