Embryo Transfer:
This is usually done after 2 - 3 days of egg recovery. You will be given a time to attend the clinic for embryo transfer. You may need to come with moderately full bladder as we conduct all embryo transfers under sonography control usually 2-3 embryos are transferred and rest can be taken for cryo preservation for future use. Before you will be discharged from the hospital detail instructions will be given to you about rest and supporting drugs. You will be asked to come to our lab for blood test to find out early pregnancy and yes we at Mayflower wish you best of the Luck!

Blastocyst Culture & Transfer

• A blastocyst is an embryo that has developed for 5 to 7 days after fertilization and has just started to differentiate.
• It has developed two different cell types and a central cavity. One group of cells will become the placenta, and the other group will become the fetus.
• A healthy blastocyst will begin hatching from its outer shell by the sixth or seventh day. Shortly after hatching from the shell, it should begin to implant into the lining of the mother’s uterus.
• In past years, the majority of embryo transfers were done on day 3 (after the egg retrieval) at the “cleavage stage” when the embryos have four to eight cells. One problem with this is that day 3 embryos normally are found in the fallopian tubes, not in the uterus. The embryo first moves into the uterus at about 80 hours after ovulation. The implantation process begins about 3 days later, after blastocyst formation and hatching have occurred.
• The other problem with transferring on day 3 is that many embryos at that stage do not have the capacity to continue development and become high-quality blastocysts.
• There are no reliable methods to determine which of the day 3 embryos will be viable long-term. Therefore, the tendency has been to transfer more embryos on day 3 in an attempt to achieve good pregnancy rates. When embryos are cultured from day 3 to day 5, some will stop developing and others (25% to 60%) will continue to become blastocysts.
• By choosing the best blastocysts for transfer on day 5, we can choose much more reliably those with the best potential for implanting and having a baby.
• In the past it was difficult to get good numbers of high-quality blastocysts with in vitro culture systems. However, advanced culture media have been developed that provide the proper balance of nutrients at the various stages of early embryo development.
• Proper culture techniques with these new media formulations yield excellent blastocyst formation rates. This makes blastocyst transfer a viable option for some couples with infertility.
• In exclusive day 5 transfers one of the issues with this is that a small proportion of couples will have embryos that are growing on day 3, but by day 5, all of their embryos have stopped developing. These patients could have had a day 3 embryo transfer, but because their embryos were kept in culture and arrested after day 3, they will not have an embryo transfer at all. This has been reported to occur in about 5% of cases if all patients’ embryos are cultured for 5 days. The ultimate outcome of the cycle may be exactly the same either way (a failed cycle), but patients would probably prefer to have an embryo transfer and then not be pregnant as opposed to being called and told that their embryos have stopped developing and therefore they will not have an embryo transfer at all.
• Most IVF centers (including ours) that perform day 5 transfers have selection criteria for deciding which cases are transferred on day 3 versus day 5. The criteria often involve a minimum number of fertilized eggs or a minimum number of good-quality embryos on day 3. In our IVF program, we typically perform day 3 transfers for all couples with three or fewer fertilized eggs, and day 5 transfers for all couples with four or more fertilized eggs.
• Do blastocyst transfers correlate with higher pregnancy rates than day 3 transfers? Yes, in most published studies, pregnancy rates are higher with blastocyst transfers when a given number of embryos are transferred (e.g., two). This is because of the higher potential for implantation of the blastocyst.
• However, the issue is complicated because some IVF centers have seen no improvement or even lower pregnancy rates with blastocyst transfers. This is because Blastocyst culture and transfer is technically more complicated and difficult as compared to day 3 transfer.
• Difficult to maintain the stable and exacting culture environment for 5 days that allows the optimal development of the embryos.
• Because of the very high implantation potential of quality blastocyst embryos, we should be cautious about the high potential for twins. Transfer of two excellent blastocysts can result in twin pregnancy rates as high as 60%. Therefore, transferring only one should be considered in young women (or in egg donation cycles) with high-quality blastocysts. Pregnancy rates in these patients can be in the 50% range with a very low risk of twins (perhaps 2%) and no real risk for triplets.
• In conclusion, blastocyst culture and transfer of one or two embryos in IVF centers that are proficient with this technique currently offer the best balance between the chances of any pregnancy ensuing and the risks involved with a multiple pregnancy.