Freezing female ova has always been more complicated than freezing male sperm, but recent developments in freezing techniques have increased the odds of achieving a pregnancy and a live birth. But freezing is only one problem in the process. Retrieval of useable ova depends on several factors, and a woman’s age is decisive here. At age 35, women’s ability to produce viable eggs falls off sharply. Not only that, but success rates in establishing pregnancies in women through in vitro fertilization falls off sharply with increasing age as well. Many women do not, however, have good estimates of their future fertility, and they often delay taking steps to freeze their eggs until they have very poor prospects for achieving a successful pregnancy. The average age for women to take steps to freeze ova in the hopes of having a child later on is 38. That’s ‘old’ by the standards of successful pregnancies.
In light of this outcome, two analysts – Heidi Mertes and Guido Pennings -- at the Bioethics Institute at the University of Ghent have argued on behalf of a campaign to get the message about ova freezing to women early. By the time a woman is in her early 30s (if not before), they think she should know the basic fertility arithmetic: younger is better when it comes to freezing eggs and that age 35 puts the prospect of a pregnancy in doubt even with the assistance of fertility clinicians. Women who wait will be “more often wrong than right” that they will be able to have a baby, frozen ova or not.
As freezing techniques improve, it is likely that more and more women will turn to clinicians for help in storing their ova in the hopes of having a child. This prospect will reinvigorate the debate about whether it is ethical to freeze eggs for ‘social reasons,’ namely for non-medical reasons. Most commentators seem sympathetic to the idea that women facing therapies that will destroy their ova should have the option of freezing some to preserve their option of having a genetically related child later on. Women who delay having children because they are pursuing a demanding job, higher education, or because they can’t seem to find the right partner do not always seem as sympathetic. Nevertheless, the demand for freezing ova is only likely to increase, but that demand should be informed by the realities of human physiology, and it is reasonable to take steps to ensure that women know what lies ahead of them, since their prospects of having children are much different than for men.
See Heidi Mertes, Guido Pennings. Social egg freezing: for better, not worse. Reproductive Biomedicine Online 2011 (23): 824-829.