You were born with every egg that you’ll ever have. Although studies suggest that there may be a process where we can create eggs; such technology is far into the future. More importantly, you’re losing eggs at a rate that far exceeds what you would guess. Current research suggests that most women will lose about 500 to 1000 eggs per month through a process of attrition called apoptosis—yet only one or two eggs each month will be capable of fertilization. A recent summary of all of the available research has shown that most women will only have about 3% of their eggs remaining by age 40.
Estimated number of remaining follicles (from birth)
Although the slope of that curve appears intimidating, the goal of this blog post is to increase your awareness and to empower you to take action. Some women are born with more eggs than others. Some women will lose their eggs at a faster rate. Most importantly, the eggs that remain in your ovaries at any given moment represent your ovarian reserve. Therefore, it is very relevant for you to consider how many eggs you have now and then plan how many (more) children you think you might someday wish to have.
This diagram shows the various stages of egg development summarized in a single ovary.
It takes an egg several months to develop from its status as a primordial follicle to that of a mature fertilizable oocyte. It is only when they reach that stage that the ovary releases the egg through a process called ovulation. Fewer than 300 of your eggs are likely to ever complete this journey. In other posts on this blog, we focus on various steps you can take to optimize the health of your developing eggs; but for now let’s focus on the future of your fertility in the months and years to come.
At least 99% of your remaining eggs are dormant—alive but not metabolically active. They have been in this resting state since you were a newborn. The eggs that are in these intermediate stages of development—which represents your fertility—can be estimated by a simple well timed blood test. Consider having your ovarian reserve tested today. Then think about how many children you envision yourself having. Consider when you will be ready to start or expand your family. By doing so, you can better estimate whether or not egg freezing or embryo banking (creating and storing embryos for future use) are steps you should be considering to assist you in creating your future family.