Everything you need to know about your eggs

Why you have only a limited number of eggs

Unlike men, who continuously produce new sperm from puberty onwards, the female store is set from the very beginning. The precursors of the eggs, the primordial follicles, reach their maximum while still in the womb. From then on their number declines continuously, a process that runs independently of contraception, pregnancies or lifestyle (Wallace and Kelsey, 2010).

In every cycle, many follicles are recruited at the same time and begin to mature. But usually only one wins the race to ovulation; all the others break down in the process known as atresia. That is why, across an entire lifetime, only around 400 to 500 eggs are released, even though hundreds of thousands were laid down.

Eggs and age: how fertility changes

The decline of the reserve is not steady. From around the mid-30s the loss accelerates, and the quality of the eggs also decreases more markedly (Faddy et al., 1992; te Velde and Pearson, 2002). Most women are most fertile between their mid-20s and mid-30s. Once the store is finally exhausted, the ovaries stop producing oestrogen and menopause begins, on average around the age of 51.

The pill myth: does contraception save eggs?

One of the most common questions is: if the pill suppresses ovulation, are eggs saved for later? The answer is no. Even on the pill, follicles are recruited every cycle. They do not mature all the way to ovulation but break down in atresia. So nothing is saved, and menopause is not pushed back as a result.

How is the egg reserve measured?

The most important lab value is anti-Müllerian hormone (AMH). It is produced by small, maturing follicles and, through a simple check, gives an indication of the remaining reserve (Dewailly et al., 2014; Moolhuijsen and Visser, 2020). In addition, antral follicles are counted by ultrasound. Important to know: AMH estimates the quantity, not the quality of the eggs, and is not an exact fertility test (Broer et al., 2014).

If you would like an indication of your current status, you can have relevant hormone levels conveniently checked from home with the At-Home Hormone Check-In Kit, including wellness guidance. You cannot change the number of your eggs, but you can support their quality through your lifestyle. You can read how in our article on improving egg quality, and which nutrients matter around trying to conceive under nutrients for fertility.

Conclusion

Your egg reserve is set at birth and declines throughout life. That cannot be changed and is not a cause for concern, but a natural process. What can be influenced is not the number, but to some extent the quality of the eggs and the regularity of ovulation. If you would like to understand your own status better, the AMH value offers a first indication, and a conversation with a health professional can help you put it in context.