A woman’s fertility is at its highest in her late teens and early twenties. For some women, having a baby at this stage of life is not an option and many now try for a family in their mid to late 30’s.
Unfortunately, when a woman is older it is more difficult to conceive and the chances of miscarriage are greater. This is because the number and quality of eggs in the ovaries declines from 35 years of age.
The effects of these changes are best illustrated by the national IVF figures, provided by the HFEA’s published data, showing that the success of IVF also declines with increasing age (Figure 1).
Figure 1. Live birth rate per IVF cycle (HFEA 2009-10 - Published 2012)
We know that the success of IVF in an older woman using eggs donated from a younger woman is dependent mostly on the age of the donor i.e. a ‘young’ egg is more fertile and the resulting embryos have a higher potential to implant.
So is it possible to put a woman’s eggs into "suspended animation" so that they don’t age with her?
The human egg is a very large cell and, until recently, the technology to freeze (and thaw) was inadequate due to damage caused by ice crystals forming within the egg. However, with advances in freezing technology we can now reliably freeze eggs using a technique called vitrification. At GCRM-BELFAST we offer fertility preservation whereby the woman goes through the IVF stimulation process but the unfertilised eggs are vitrified.
The technology is relatively new but the results are encouraging, such that units around the world are achieving 25% pregnancy rates using vitrified eggs. This compares favourably with the success rates of IVF at a given age (see Figure 1, above). The number of babies born following these procedures is increasing. It is important to realise that the decline in fertility is due to the "age of the eggs" and therefore fertility preservation is most effective if the eggs are frozen when the woman is young. However, it remains an option for women in their mid-30’s or older who do not want to have a family just yet. If you feel that fertility preservation might be for you and would like to learn more then please click here for a factsheet.