What is Blastocyst Transfer in IVF Treatment ? In simple words, blastocyst is an embryo that is five or six days old. It is a highly differentiated, highly attached embryo that is ready to attach to the uterine wall. A decade ago, doctors would transfer day-three embryos in IVF cycles. However, now fertility specialists believe that transferring better developed embryos or blastocyst implantation will lead to a higher IVF success rate.
What Does a Blastocyst Look Like?
How does a Blastocyst look like?
When examined under a microscope, a blastocyst embryo is very different from a day-three embryo. A blastocyst embryo has a fluid-filled cavity in the middle, which is termed as the blastocoel. Another area, housing a dense collection of cells, is called the inner cell mass which later develops into the foetus. A third bunch of cells, near the central cavity, eventually form the placenta.
What is it?
What is a Blastocyst Transfer in IVF A part of the IVF treatment, a blastocyst transfer is an assisted reproductive technological process whereby a day-five embryo is transferred to the uterus leading to a higher success rate and lessen the risk of multiple pregnancies. An embryo that survives for five days or more has a higher chance of leading to a successful pregnancy and is more viable for implantation. Also, many studies have pointed out the benefits of blastocyst formation and culturing.
In conventional IVF, embryos are grown for two to three days before they are transferred back into the uterus. By this stage of development, the embryo has between four and eight cells inside the shell also called the zona pellucida. These cells must continue to develop inside the uterus for four to five additional days before they become blastocyst embryos that are ready and capable of implantation. Within 24 hours after hatching, embryo implantation after IVF begins as the embryo invades into the uterine lining.
Most IVF cycles will produce several embryos. But, as blastocyst embryos have a higher implantation potential than less advanced embryos, only a few of them are transferred. Often, only one good quality blastocyst embryo is recommended for transfer as against two or more. Remaining blastocysts are frozen for later use. This is good news for IVF patients, and something your fertility doctor will fully explain to you during your consultations. The blastocyst embryo releases HCG hormone which leaks into the mother’s blood as the embryo implants.
Benefits of a Blastocyst Transfer
- Easier implantation: Using a blastocyst makes the implantation easier and smoother. Placing a blastocyst directly into the womb, optimally timed, in a medicated cycle, between day 19 and 21, is an easier prospect for the hormonally primed uterus.
- Higher chance of a live birth: If the patient is under 35 years of age, chances of a live birth are higher than an early-stage embryo transfer.
- Reduced risk of multiple births: When embryos are developing in an IVF lab, the embryologist or the fertility doctor can determine which embryos are the best ones for transferring. Only those few embryos that may implant successfully are chosen by the doctor. Eventually only one or two blastocyst embryos are transferred, leading to a successful pregnancy. This eliminates the risk of high-order multiple pregnancies, such as triplets or quadruplets.
- Accurate genetic testing: Usually, genetic testing or screening done on a day-three embryo might not give accurate results. But genetic screening performed on a blastocyst embryo will give extremely accurate and reliable results.
Factors affecting Blastocyst Transfer success rate?
A lot of factors need to be accounted for while doing a frozen blastocyst transfer. All patients cannot opt for a blastocyst transfer.
A few of them are as follows:
- Patient’s medical history and age: A frozen blastocyst transfer is recommended for patients below the age of 35. Also, the patient’s medical history and lifestyle is significant while opting for a blastocyst transfer.
- Number of embryos: At times, there might not be enough embryos to freeze. Freezing of embryos for a second attempt is often overlooked by IVF patients. The fact is that frozen embryo transfers, particularly those using blastocysts, are almost as successful as fresh ones.
- Quality of embryos: At times, embryos may not get to day-five. The doctor may then decide to transfer a younger embryo.
Cost of Blastocyst Transfer
Depending on the number of embryos to be frozen and the monitoring, testing involved, the cost of a blastocyst transfer can range anywhere from Rs 50,000 to Rs 100,000 in India.
A blastocyst transfer is an ideal route to improve the IVF success rate and has multiple benefits as well. It reduces risk of multiple births, leads to easier implantation, and has a higher chance of a live birth. It is recommended for patients who are below the age of 35.