Meaning of Blastocyst: A Blastocyst is an embryo which in which cells have differentiated (divided). Blastocyst is formed on the day 5 or 6 after the fertilization.
Normally in conventional IVF, the embryos are transferred on day 2 or day 3 after egg collection and insemination. It is also called as day 2 or day 3 embryo transfer. In blastocyst transfer the blastocyst is developed up to day 5 after the process of insemination.
Most of the fertilized egg lead to the formation of a 3 day old embryo. On the other hand, only 40% of them tend to develop into a blastocyst. Because of this the blastocysts are a more of a “specific” group of embryos which lead to better chances of maintain a pregnancy.
Why Blastocyst Transfer?
In blastocyst culture, the embryos are allowed to grow in the laboratory for a longer duration. In this extended time period the embryo undergoes development. Because of this excess time the embryo is in the laboratory, it is possible for the IVF experts to choose an embryo which has the best potential to grow inside the womb. Hence, blastocyst culture helps to increase your chances of conceiving and maintaining a pregnancy. If this procedure is used in a young woman from the age group of 20 to 30 years, 80% pregnancy rates may be obtained. The chances of loss of pregnancy or miscarriage are only 5 to 10 %.
Advantages of Blastocyst Transfer for IVF:
1. Increased Chances of Maintaining the Pregnancy:
In the conventional IVF embryo transfer was done on after 2 to 3 days following fertilization. Naturally, in 2 to 3 days embryo travels in the fallopian tube. So it normally reaches the uterus after 3rd day. By this time, the blastocyst is formed. The implantation process is started at this point. The endometrium is better prepared on day 5 to receive the embryo, as this is the most natural time for the embryos to be in the womb of the mother. Following the same principle, as blastocysts are transferred on the day 5, the conditions in womb are favorable. Hence the chances of implantation and maintaining of pregnancy are marginally increased.
2. Reducing Possibility for Multiple Pregnancies:
In conventional IVF, more number of embryos is transferred to increase the chances of a viable pregnancy. Many times it results in multiple pregnancies. The most important benefit of blastocyst culture is that the number of multiple pregnancies is reduced. This is because only 1 or maximum 2 embryos are transferred after blastocyst culture. As the most competent embryos are selected for the transfer. Fewer embryos can be thus transferred and still high pregnancy yield can be expected. It is the method of choice if the patient specifically requests single embryo transfer.
It is exciting for us to be able to offer our patients this promising state-of-the-art technique, as it provides us the ability to further tip the balance of success versus risk in favor of couples when we assist them in their pursuit of parenthood. Contact our specialist to discuss!!