Blastocyst Transfer – The Most Effective Way to Increase Your Chances of Conceiving

What is a blastocyst transfer? There are so many terms to learn when you’re undergoing IVF. Indeed, one can certainly become an expert in the entire procedure, especially if they’ve undertaken it more than once, as many do. The patient will quickly learn the names of drugs necessary for the process, medical instruments used during the procedure, and a variety of other words and phrases that they’ll hear throughout the steps associated with IVF.

The patient will also become familiar with variations of the procedure, as different clinics and doctors may have slightly different steps that they follow in the IVF process. The main goal of this process is to help a couple conceive by creating an environment in which fertilized eggs can thrive. This usually involves some sort of stimulation of ovulation, which is the release of eggs from the ovaries. Once the eggs are harvested, they’re combined with sperm in a lab dish, and then one or more of the resulting embryos are implanted into the uterus.

The word “blastocyst” is certainly one term that is frequently used. A blastocyst refers to an embryo that is cultured in the IVF lab for about 5 to 6 days. In general, embryos remain in the laboratory incubators for that length of time so that there is a better chance for them to implant in the uterus after being transferred.

IVF treatment usually begins with the egg retrieval procedure. This is followed by insemination of the eggs and then incubation. After a few days, the embryos will be transferred into the uterus. The entire process usually takes about two weeks.

Some couples may opt to have their blastocysts biopsied before they’re transferred. This helps determine the health and quality of each embryo so that only the best ones are chosen for transfer. In some cases, blastocyst biopsy may also be used to screen for genetic diseases or abnormalities, such as Down syndrome.

What is blastocyst transfer and how is it done?

With blastocyst transfer, embryos are cultured in the lab for 5 to 6 days, as previously stated. This is as opposed to 3 days, which in the past was when doctors used to transfer the embryos to the womb. Embryo Transfer can still be done on day 3 for a few different reasons, but most believe that it is best to wait until Day 5 whenever possible.

The main benefit of waiting until Day 5 is that it allows the embryo more time to develop. This can be important because embryos that are transferred on Day 3 are often not as developed as those transferred on Day 5. This can lead to a lower success rate for Day 3 transfers.

In addition, waiting until Day 5 gives the doctor a better idea of which embryos are the strongest. This is because, on Day 5, the embryo will have reached the blastocyst stage. At this stage, the embryo’s cells have begun to differentiate into two different types: those that will become part of the baby and those that will become part of the placenta.

As you are ready for the transfer, the best blastocyst(s) will be chosen from those being cultured in the lab, and those are the ones that will be inserted into the womb. This however does not ensure that pregnancy will occur. The blastocyst must attach itself to the wall of the uterus after embryo transfer to establish and maintain a pregnancy.

Blastocyst development and formation

For IVF patients in the distant past, it was accepted practice to transfer embryos after 2 to 3 days of development. Given the advancements in embryo culture techniques with blastocyst transfer, this is undoubtedly why the procedure is much more successful now than it was in the early days of in vitro fertilization.

In reality, many embryos may not make it to day 5. As a matter of fact, with standard IVF culture conditions in place, only about 25% to 60% get to that point. Why? Primarily because some are inherently compromised and would, nevertheless, not result in pregnancy under “normal” circumstances. They likely possess chromosomal abnormalities or other underlying developmental genetic problems.

Other embryos may be apparently normal but stop developing after a few cell divisions anyway. Such developmental arrest often reflects suboptimal uterine receptivity or poor embryo-endometrial interactions, both of which are common in older women undergoing IVF. In fact, studies have shown that about one-third of all arrested embryos actually have proper 23-chromosome sets and are chromosomally normal. The question, then, is why can’t they continue to develop?

There may be many reasons for this developmental arrest. One theory is that these embryos have a genetic predisposition toward incompatibility with the mother’s uterine environment, which includes hormonal conditions inside the womb. These conditions can be altered by using specially-designed culture media and techniques, which is the basis for what’s called extended or delayed embryo culture until transfer (ECC / DEC).

As a result, blastocyst transfer, whenever possible, is preferred by most of today’s top infertility specialists given its track record of improving the chances of pregnancy, especially when only a single embryo is transferred. This strategy also helps avoid multiple births by upping the chance of a single embryo implanting in the womb, resulting in a successful and safe outcome.

Is blastocyst transfer right for everyone?

Many clinics are promoting blastocyst transfers for the majority of their patients. Younger, otherwise healthy women are excellent candidates for blastocyst transfer, as are women who have produced excellent quality embryos in previous cycles where a day 3 transfer did not result in implantation. While those who produce fewer eggs may have a greater chance of undergoing an embryo transfer by having it performed on day 3, the reality is that embryos which do not make it to day 5 or 6 are extremely unlikely to implant irrespectively. As a result, even with the risk of having nothing to transfer on day 5, patients are spared the heartache of a negative outcome from the transfer of an ultimately non-viable embryo.

Do you have more questions about blastocyst transfer? We can provide answers as well as help you better understand the entire IVF process. For more information or to schedule an appointment, call our office at 732-339-9300.

We look forward to helping you achieve your dream of parenthood!

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