we will address a hypothetical individual looking to enhance their egg quality for the sake of clarity. However, this information is equally important for partners or potential donor parents, so don’t leave just yet!
Let’s talk about eggs. If you have been trying to conceive for a while, you know that timing is everything. You need to have sex during the fertile window around ovulation, which only occurs a few days every month. Otherwise, your chances of getting pregnant are slim to none. Most fertility advice focuses on helping you identify and maximize this window.
Unfortunately, the math of conception is not always as straightforward as we would like it to be. Fertilizing an egg with sperm does not always result in a baby. Once the egg is fertilized, it becomes an embryo, but only about a third of fertilized embryos make it to the baby stage. Eggs of higher quality are more likely to survive past the embryo stage.
Therefore, if you are struggling to conceive, timing sex correctly is only part of the equation. Taking steps to optimize egg quality is just as crucial, if not more so.
What exactly do we mean by “high-quality” eggs? Essentially, they should have good genes. Before maturation, eggs are known as oocytes, and they contain 46 chromosomes, which are long molecules that carry genetic information. During the egg’s maturation process, called meiosis, these 46 chromosomes consolidate into 23 chromosomes. The sperm contributes the other 23 chromosomes, creating a unique genetic makeup for the embryo. However, not all eggs pass through meiosis with the correct number of chromosomes. Eggs with chromosomal abnormalities are known as aneuploid eggs. Even healthy, fertile women may have cycles that produce aneuploid eggs, which usually fail to fertilize. If an aneuploid egg does fertilize, it often does not survive, resulting in a miscarriage. In fact, chromosomal abnormalities are responsible for 41% of miscarriages.
So, can egg quality really be improved?
Women are born with all the eggs they will ever produce in their lifetime, so egg quantity is a fixed factor. For a long time, scientists believed that egg quality was also fixed, and aneuploid eggs were the result of accumulated damage to the egg due to the aging process. While age does affect egg quality, we now know that chromosomal damage is more likely to occur during meiosis. Any errors during this process can result in missing or extra chromosomes, which is not ideal. However, the good news is that meiosis offers us an opportunity to influence egg quality by supporting the egg’s mitochondria. These cell structures convert fuel sources into cellular energy, which powers the demanding process of meiosis. Boosting the egg’s mitochondria can support meiosis and increase the chances of producing a chromosomally normal egg. We will explore how to do this in the following section.