FERTILITY PRESERVATION
after 2 years. We prefer automatic payments for storage fees because it helps us keep in contact with you. You must tell us if you change address.
Risks Frozen sperm and embryos are stored in thin plastic straws immersed in liquid nitrogen. Cross-contamination of straws by viruses such as Hepatitis or HIV is a theoretical risk although it has never been reported. As a precaution we store sperm for men positive to Hepatitis B or C or to HIV in a separate bank. There is a very small risk that a liquid nitrogen bank will fail, causing the sperm, eggs or embryos stored in it to perish. Bank failure has been reported occasionally around the world. We take reasonable precautions but cannot be held responsible for the loss of sperm, eggs or embryos from bank failure. Obtaining eggs and embryos for storage carries the risks associated with the relevant parts of IVF treatment, which are covered on page 67.
Cost Sperm storage before cancer treatment or similar treatment is nearly always publicly funded if you do not have a child already. You generally have to pay for sperm stored as back up for fertility treatment, and always for storage before vasectomy. Egg or embryo storage before cancer treatment or similar may be publicly funded depending on the circumstances – most of the usual rules for eligibility for publicly funded IVF treatment apply. Egg storage for social reasons and ovarian tissue storage needs to be privately funded; these prices can be found on our website.
If you have embryos frozen, the chance of pregnancy is similar to that from using fresh embryos. About 95% of embryos survive freezing and thawing. Eggs are more prone to damage from freezing and thawing than embryos, and there is more variation in egg survival between individual women than there is for embryo survival. For some women 90% or more of their eggs survive, while for others the rate may be closer to 50-70%. If an egg survives, then most people have normal embryo development, but for a few embryo development may be poor. Unfortunately, there is no way to predict this. The most important factors influencing the chance of having a child is your age when the eggs were frozen and the number of eggs or embryos available. Fertility Associates has a discounted fee for women who want to do a second or third egg freezing cycle. Several experts have calculated the chance based on the number of eggs stored and the age of the women when she stored her eggs – an example is shown in Figure 11, using data from a scientific publication by Doyle and coauthors in the journal Fertility & Sterility. For instance, a 36 year old woman who has 8 eggs frozen is calculated to have a 45% chance of having a child using these frozen eggs.
Using frozen eggs When you decide to use your frozen eggs, call the clinic and make an appointment to see your doctor. You and your doctor will then plan your cycle. The eggs will be thawed, fertilized, grown to the blastocyst stage and suitable embryos frozen at the blastocyst stage. When you have one or more frozen blastocysts, you’ll be able to have an embryo transfer cycle. The time between your doctor’s appointment and a thawed embryo transfer cycle is typically two months or so.
PREDICTED CHANCE OF A CHILD BY NUMBER OF EGGS FROZEN (from Doyle et al 2016) 100% 90%
30-34 years
80%
35-37
70%
38-40
60%
41-42
50% 40% 30%
Chance of a child using stored sperm, eggs or embryos If you have frozen sperm, the type of treatment to use depends on the number and quality of the sperm stored. IVF and IUI pregnancy rates are the same using frozen sperm and fresh sperm.
20% 10% 0%
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9 10 11 12 13 14 15 16 17 18 19 20
Number of mature eggs frozen Figure 11.
PATHWAY TO A CHILD
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