Oocyte cryopreservation, or egg freezing, is a relatively new technique used in assisted reproductive therapy. When a young woman’s eggs are cryogenically frozen and used later for in-vitro fertilization, they are as successful in resulting in pregnancy rates and birth rates of healthy babies similar to rates achieved by IVF cycles that use fresh eggs.
A recent study by the Practice Committee of the American Society for Reproductive Medicine has replaced a previous report five years ago. In 2008, the report indicated that egg freezing was an experimental technique, and it should only be used as such.
Almost one thousand research papers have been written on the subject, however there were only a handful of randomized controlled trials (RCT) that have been conducted. Nevertheless, the Committee observed that there was enough evidence to demonstrate success rates for egg freezing. These success rates apply specifically to young, highly selected populations of women.
It is important to note that the age of the woman at the time of egg freezing is one of the most important and significant criteria. The Committee stresses that success rates for cryopreservation of eggs appears to decline with maternal age at a rate commensurate with the success rate experienced with eggs that are harvested fresh.
The Committee also suggests that oocyte cryopreservation may be a viable source of eggs for couples who need donor eggs in order to become pregnant. Additionally, egg freezing may be used to preserve fertility for individuals who have become infertile after undergoing treatment for other diseases such as cancer, or have genetic conditions that are incompatible with fertility. Even IVF treatment that has failed due to the unforeseen inability to obtain sperm can benefit from oocyte cryopreservation.
It is important to note, however, that general use of egg freezing for elective use is not fully endorsed. The Committee claims that there is still inadequate information on efficacy, safety, cost-effectiveness, and psychological and emotional issues that may result from using egg freezing in the context of assisted reproductive therapy, oocyte donation or other related applications.
According to the report, the advertising and promotion of this technology “for the purpose of deferring childbearing may give women false hope and encourage women to delay childbearing. Patients who wish to pursue this technology should be carefully counseled.”
The technology of oocyte cryopreservation has great potential, and has plenty of room to grow. It is well beyond the experimental stage, and can be used to treat infertility in young patients who fit the qualifying criteria. Since pregnancy rates, as well as the well being of the resulting babies, are now similar to those of IVF with fresh eggs, this technique can be applied in assisted reproductive therapy with a greater level of confidence.