Answer from: Saghar Kasiri, Clinical Embryologist
Because the egg freezing process has been so successful in recent years, banks like us frequently freeze eggs and thaw eggs and get successful pregnancies as a result. It again goes back to the quality of the eggs but in the past because we couldn’t freeze eggs very successfully, the fresh cycles were always more successful in giving pregnancy than frozen cycles of eggs so if you had egg donation or if you froze your own eggs, the frozen eggs may have not been that successful. Nowadays this is completely changed. We have a very good survival rate of eggs after freezing. We have a very good fertilization rate, blastocyst development and also successful pregnancy; for example we know from our own bank where we provide a good quality donor eggs, we have a 95% survival of our eggs we have a very good number of fertilization around 86% and we have over 75% pregnancy rate with the eggs that we freeze and provide to patients that need it.
The reason for this success is because the eggs are from women that are younger – between the age of 20 to 32 and therefore these are healthy eggs that have been screened and will survive the process very well and produce pregnancy.
If you are freezing your own eggs and would like to know the success rate of it in the future it all goes back to what age you were, how many eggs you’ve frozen, the quality of the eggs you’ve frozen, the technology that’s used in the lab that you freeze eggs.
If you would like to freeze your eggs for the future, it is very important that you go to a clinic that is an expert and has experience in freezing eggs and also thawing or warming the eggs afterwards for the use in an ICSI cycle.
Answer from: Andrea Sánchez Freire
Freezing techniques have been improving over the years, with the introduction of vitrification in laboratories we can freeze oocytes knowing that we will have a good survival rate. Oocyte vitrification survival is around 90%. Although this also depends on the quality of the oocyte and the age of the patient, studies confirm that the survival rate of frozen eggs increases in young patients.On the other hand, a good number of frozen oocytes will give the patient more chances to have a good cycle and get pregnant. Egg vitrification is a highly demanded and recommended technique nowadays, being used for the preservation of fertility for social or medical reasons.
Answer from: Melvin H. Thornton, Associate Professor
The survival rates with the vitrification process which is the standard process used now, we always tell patients that about 80 to 90% of the eggs that are thawed will survive. Then, more importantly, those fertilization rates are the same as fresh eggs which are about 90%. So if that egg does survive which is about an 80 to 90% chance it will survive, the fertilization rates are the same as a fresh and the pregnancy rates are the same as a fresh egg.
Answer from: Ioannis Zervomanolakis, PhD
During the vitrification procedure, we make sure that we have a very high survival rate. And this survival rate of 90% means that 9 out of 10 oocytes are going to survive. And around 7-8 out of 10 oocytes are going to be fertilized. That means that we are very proud of the high survival rate that we can achieve through the vitrification of oocytes.
Answer from: Jessica Subira, M.D. Consultant in Gynecology, Sub-specialist in Reproductive Medicine
As we’ve explained before also vitrification has allowed for a very good oocytes survival rate for young patients that’s below 38. Survival rate is around 85-90 so that’s a very good survival rate but we also know again that this depends on the clinic, on the expertise of the people performing the procedures. In general that would be the oocyte survival. For patients above 38, we know that there is a slight reduction in oocyte survival that could go down to 80% something like that. In general terms if you freeze 10 eggs, you would expect 9 out of 10 surviving the process and be viable for use for IVF.
How many frozen eggs survive thawing?
Frozen eggs need to be thawed by an embryologist before they are fertilized with a partner or donor’s sperm. What are the chances that they survive and will be fertilized during your IVF process?