One of the primary reasons women have their eggs frozen is to preserve younger, more viable eggs against a future desire to start a family. The primary target age for women wishing to freeze their eggs is usually between the ages of 30 and 40 (and often between 35 and 40), when it has become apparent that a woman is choosing to delay having a child or children for career, educational, personal, or illness reasons. After about the age of 40, fertility and egg viability begin to decline steeply.
While younger women in their 20s could choose to freeze their eggs, it is generally in order to preserve healthy eggs before the woman undergoes a medical treatment that could render her sterile or less fertile (i.e. radiation treatment for cancer) or because she has a family history of premature decrease in ovarian function.
The regularity or irregularity of your menstrual cycle does not affect the number of eggs you have, and your eggs can still be stimulated in the same way as women who have regular menstrual cycles.
You can never really freeze too many eggs, and we recommend that cryopreserving at least 6-8 eggs for each pregnancy attempt is ideal (for women under 40, we normally harvest 10-15 eggs per cycle to allow for two pregnancy attempts). Statistically, some eggs will not be viable after extraction and some eggs will not be viable after the freeze/thaw cycle, so increasing the number of eggs you freeze also increases the chances of successfully getting pregnant.
That being said, some women simply produce more eggs than others for a variety of reasons including age, genetics, health history, and personal physiology. Younger women are more likely to produce the desired number of eggs from one stimulation cycle whereas older women or women who naturally produce fewer eggs might have to undergo a second stimulation cycle to reach the desired number of eggs for freezing.
There are always risks involved in medical procedures, and each woman needs to closely examine the risks and weigh them against the possible benefits in order to make an informed choice. Fortunately, adverse reactions to any of the processes and procedures involved in stimulating eggs and egg retrieval are rare, and we will be happy to further explain any possible risks based on your age, health, and other factors unique to you. In addition, our experience, knowledge, and long practice in egg retrieval and egg freezing further reduce risk to yourself and to your eggs.
One of the greatest non-medical risks in egg cryopreservation is the sense of complacency a woman can get from knowing that her eggs are frozen and waiting. That complacency could cause her to wait longer to try to get pregnant than if she did not have that safety net in place, and the results could be that she is then not able to get pregnant due to age or other circumstances.
The field of egg cryopreservation is new enough that we don’t yet have good statistics on how long a human egg can be stored and still be viable. We already know that frozen eggs can remain viable for months, and eggs from younger women can remain viable for years. There is evidence from animal studies that egg viability may decrease over time during storage. However, the Egg Freezing Center has seen the healthy birth of a child whose mother froze her eggs at the age of 43 and delivered at the age of 47.