People frequently ask if their egg quality can be tested to understand their reproductive potential. Egg quality refers specifically to the genetic viability of the egg, meaning its chromosomal integrity and health. A high-quality egg possesses the correct number of chromosomes, necessary for successful fertilization and the development of a healthy embryo. Currently, a direct, non-invasive test to measure the genetic quality of an egg does not exist. Determining an egg’s quality requires retrieval from the ovary and subsequent analysis, often after fertilization (Preimplantation Genetic Testing). Therefore, clinical fertility assessments focus instead on proxy measures that estimate the remaining egg supply.
Understanding Egg Quality Versus Ovarian Reserve
The distinction between egg quality and ovarian reserve is a common source of confusion in fertility discussions. Ovarian reserve is a quantitative measure, referring to the total number of eggs remaining in the ovaries. It represents the size of the remaining egg supply pool. This measurement helps predict how many eggs might be retrieved during an assisted reproductive technology cycle, such as in vitro fertilization (IVF).
Egg quality, in contrast, is a qualitative measure related to the genetic health of each individual egg. A high proportion of eggs with abnormal chromosomes (aneuploidy) indicates poor egg quality, increasing the likelihood of implantation failure or miscarriage. While ovarian reserve varies among individuals, egg quality is most strongly correlated with the person’s age. For instance, a younger person with low ovarian reserve may still release high-quality eggs, but low reserve in an older individual suggests a lower probability of a genetically normal egg.
Common Tests Used to Measure Ovarian Reserve
Since egg quality cannot be tested directly, clinicians assess ovarian reserve using specific biochemical and imaging tests. These tests estimate the remaining follicle pool and the ovaries’ potential response to stimulation. The Anti-Müllerian Hormone (AMH) test is a blood draw that can be performed at any point in the menstrual cycle. AMH is secreted by the granulosa cells of small, growing follicles within the ovary. A higher AMH level indicates a larger supply of remaining eggs, making it a reliable marker of ovarian reserve.
Another assessment involves measuring Follicle-Stimulating Hormone (FSH) and Estradiol early in the menstrual cycle, typically on day two or three. High basal FSH levels suggest the pituitary gland is working harder to stimulate the ovaries, signaling diminished ovarian reserve. Estradiol is measured simultaneously because its early elevation can artificially suppress FSH levels, potentially leading to a falsely normal result.
The Antral Follicle Count (AFC) is performed via transvaginal ultrasound. The AFC measures the number of small, fluid-filled sacs, or antral follicles, visible in both ovaries. Since these follicles each contain an immature egg, the total count provides a direct quantitative measure of the resting egg pool. A higher AFC is associated with a greater ovarian reserve and a better predicted response to ovarian stimulation medications.
Lifestyle Factors That Influence Egg Quality
While age is the most significant factor affecting egg quality, lifestyle choices influence the health and chromosomal integrity of the eggs. The primary mechanism involves protecting the egg’s DNA and its energy-producing components, the mitochondria, from damage. Maintaining a healthy weight is important, as both being overweight and underweight can create hormonal imbalances that negatively affect egg development.
Targeted nutritional supplementation and a diet rich in antioxidants support egg health by combating oxidative stress. Antioxidants, such as Vitamin C, Vitamin E, and Coenzyme Q10 (CoQ10), help protect the cellular components of the egg during maturation. Avoiding toxins is also important, particularly stopping smoking, as cigarette chemicals directly damage the DNA within the eggs. Managing chronic stress is a modifiable factor, as prolonged stress can disrupt the hormonal balance necessary for optimal ovarian function.