Egg Freezing / Egg Vitrification / Egg Banking
Egg freezing or vitrification is becoming a standard procedure in most IVF labs around the world. There have now been thousands of babies born showing the safety of the procedure. There will be fine tuning over time to improve survival of the eggs but the system is reliable enough to proceed. With this improvement in egg survival, new ways of using egg banking have arrived.
Egg Banking for Delaying Childbearing
This has been profiled many times in the general press. The biggest question is, how many banked eggs will it take to produce a reasonable chance of having a baby? Those numbers are slowly being determined but we do have a base to go on by looking at delivery rates with fresh eggs. We know that the number needed is much lower for women under 35 and after 37 the number needed increases rapidly. The key here is that the younger you are when the decision is made the more likely it is to be successful and the more eggs stored the more likely that a baby will be born.
Egg Banking for Cancer Patients
This was the original idea behind egg banking. The method is the same however it tends to be more rushed due to limited time before the start of chemotherapy or radiation therapy.
Egg Banking for Male Factor Infertility
Sperm freezing has been practiced for well over 50 years. However, there are large loses of sperm in the freeze and thaw process. This generally is not a problem since a normal sample has millions of sperm. Even in poor samples such as from testicular biopsies there are dozens to thousand of sperm. The problem is when we only have a couple of vials of sperm to work with. After thaw and use of the sperm, the remainder is usually thrown away. This is because of experience showing poor results with a second round of freeze and thawing. With egg banking, we can collect eggs from more than one cycle and process them all together to make better use of the sperm in cases were we have limited samples frozen.