By Dr Andrew Zuschmann, fertility specialist at City Fertility Sydney Miranda.
Some people ask: “If I freeze my eggs, does it guarantee I will be able to have a baby when I want to?” The straight answer is that there is no guarantee of having a baby, whether you use fresh or frozen eggs, because there are many other factors that contribute to a successful pregnancy. Unfortunately, there will always be a percentage of people who have difficulty falling pregnant, regardless of whether they use fresh or frozen eggs. Factors such as age, lifestyle and medical conditions all play a significant role.
However, if you are considering pregnancy later in your reproductive life (i.e. after age 35), freezing your eggs might just give you a better chance of success when you do try. The primary reason is due to the “younger and healthier” qualities of your frozen eggs.
Females are born with their lifetime supply of eggs, which naturally decline gradually in quantity and quality from the age of 25 until being almost non-existent by the time of menopause. For example, if you freeze your eggs when you are 30 and then decide to try to have a baby when you are 40 using your frozen eggs, the eggs will have the qualities of when you were 10 years younger (30).
In addition, the process of freezing female eggs has advanced rapidly over the past 10 years, and studies report fertilisation and embryo development rates for frozen eggs that are comparable to those for fresh eggs.
The main points to consider are:
- Timing: if you would like to delay having children, but are worried about your advancing age impacting your egg quality.
- Medical conditions: if you have a genetic disorder, e.g. a medical condition such as endometriosis, a family history of premature menopause, or if you have been diagnosed with cancer and need to undergo chemotherapy.
- Uncertainty: if you are not sure whether or not you want children at all, but would like more certainty until you are ready to make the decision.
Egg freezing involves a woman’s mature eggs being developed and removed using standard IVF techniques. This process typically involves three stages of treatment: pituitary suppression, ovarian stimulation and egg retrieval.
City Fertility uses the “vitrification” method for freezing eggs. The process involves cooling the egg(s) so rapidly that water molecules do not have time to form damaging ice crystals and instead instantly solidify into a glass-like structure. The concept is based on the idea that if the cell is dehydrated to a certain degree and then cooled quickly enough, everything will “freeze” in place, and damage will not have time to occur.
Compared with traditional slow-freezing methods, vitrification of eggs at City Fertility Centre is delivering enhanced egg survival and fertilisation rates approaching those of freshly retrieved eggs. A study published in Human Reproduction in 2010* also supports this position.
City Fertility follows guidelines recommended by the National Health and Medical Research Council regarding egg storage. Eggs can be stored for up to 10 years.
When the right time comes to use the frozen eggs, they are thawed and fertilised, and embryos are created. The embryo is transferred back to the woman, and hopefully a successful pregnancy results. Any extra embryos created can again be frozen for additional attempts if unsuccessful, or for siblings if successful.
Making the decision to freeze eggs can be a difficult one for some. The counselling staff at City Fertility Centre are available at any time to help patients make a decision regarding their treatment.
Unfortunately, no one is guaranteed to have a baby, whether they are using fresh or frozen eggs. There will always be a percentage of people who have difficulty falling pregnant, due to a variety of reasons.
For more information, please refer to our page: Egg Freezing or download our Egg Freezing Fact Sheet.
*Rienzi. L, et al, 2010, “Embryo development of fresh versus vitrified metaphase II oocytes after ICSI: a prospective randomised sibling-oocyte study”. Human Reproduction Vol.25, No.1 pp. 66-73
