It's very common to use donor gametes for treating infertility, and we have been using donor sperm samples to treat male infertility for many years routinely. In the past, we used to use fresh sperm samples, but when we realized how dangerous this was, because of the risk of transmission of HIV, it has now become compulsory all over the world to use only frozen sperm samples from sperm banks . These can be tested and quarantined to ensure patient safety.
However, we seem to use a double set of standards when we talk about the other set of donor gametes - donor eggs. Traditionally, we've used fresh eggs for donor egg IVF and this was because we did not have the technology to freeze eggs well in the past. Freezing involved slow freezing or slow cryopreservation and lots of eggs would die as a result of the freeze thaw process. Because this was so inefficient, we were forced to use fresh eggs when doing donor egg IVF.
However, technology has improved dramatically and with vitrification, it's now possible to freeze eggs efficiently . Survival rates are nearly 100% in an experienced clinic which has expertise with freezing and thawing eggs. This means that it's now possible to routinely use frozen eggs when doing donor egg IVF treatment. This is far better for everyone concerned - the donor; the patient; and the doctor !
It's much more convenient for the donor , because she can be superovulated according to her natural cycle , and we don't need to synchronize ( match) her cycle with that of the recipient. It's much easier for the patient , because she's confident that since we are using frozen eggs, the donor has been tested and screened for infectious diseases.
It's much better for the doctor as well, because the risk for cancellation of the cycle is now zero . Because we are using eggs, we can guarantee the patient that we will have at least 10 mature eggs for her donor egg IVF cycle, which means there's a very high probability that we will have at least 2 good quality blastocysts to transfer. On the other hand, when we use fresh eggs, we can never predict in advance how well or badly a particular egg donor will respond to the medication in a given cycle . If the egg donor doesn't grow enough good quality eggs, the poor patient is forced to either cancel her cycle ; or accept a much higher risk of failure. If the egg donor's biological response is poor in the fresh cycle , the embryos generated from her eggs will be of poor quality, and because this is a biological variable, there's nothing much the doctor can do about this.
The patient also has much more peace of mind , because it's much easier now for the doctor to be able to match the physical characteristics of the recipient and the donor because now he has a much wider pool of frozen donor eggs to choose from. Even better, there's no waiting list, and treatment can be started whenever the patient is ready, and when her cycle starts.
The doctor's life has also become a lot easier . In the past, we had to synchronize cycles for the egg donor and the recipient, and it hard to do this precisely. There was often a lag, because of a mismatch between the speed at which the patient's endometrial lining was growing , and how fast the egg donor's eggs were growing. This mean meant that pregnancy rates were often compromised.
However, now that we can use frozen donor eggs, we don't need to worry about synchronizing or matching cycles at all. We can precisely time the embryo transfer at the optimal time, because this is now completely dependent on the patient's uterine lining . We wait until her endometrium is ready , and only then do we go ahead and thaw the donor's eggs; fertilsie them; and then transfer the embryos into a ripe endometrium. This is a much more efficient use of precious donor eggs and has a much higher pregnancy rate because the patient's endometrium is optimally receptive.
While it's true that it does take time for clinics to master this new technology , and that not many clinics have enough experience with using frozen eggs as yet, the fact remains that this experience will be acquired very quickly , because lots of clinics are routinely vitrifying embryos all the time .
Even better, vitrification is simple, and doesn't require complicated or expensive equipment.
It's a matter of time , that just like using fresh donor sperm samples is now illegal, using fresh donor eggs will also become obsolete . As doctors get more experience with freezing eggs, they will find ( as we have) that whether you use fresh donor eggs or vitrified donor eggs, the fertilisation rate and pregnancy rates remain exactly the same.
As patients become more aware about the advantages of using frozen donor eggs ; and the risks and disadvantages of using fresh eggs, they will soon start insisting that their IVF clinic use only frozen donor eggs ! A lot of IVF doctors still insist that the pregnancy rate with fresh eggs is better than with frozen eggs. Yes,it is harder to freeze eggs ( as compared to sperm and embryos), and many clinics are not good at doing this, which is why they bad-mouth the technique. However, once they master the process and get over the learning curve, they will find that frozen eggs have a success rate which is as good as with fresh eggs.
Need help in getting pregnant ? Please send me your medical details by filling in the form at www.drmalpani.com/free-second-opinion so that I can guide you !
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