Mom and Baby Magazine Interview - Dean Chen Junkai

Talking about non-invasive PGT-A (Embrace). Every grain is precious. Do not give up any embryo with potential for pregnancy

The advancement of detection technology has benefited many infertile patients who have undergone IVF treatment! Nowadays, even embryos that are not of good quality and are not suitable for chromosomal biopsy have a chance to be implanted thanks to non-invasive PGT-A (Embrace)!

Implantation of chromosomally normal embryos

Since embryo quality is related to implantation rate, good embryos must be selected for implantation. Women under the age of 35 who are planning to have a baby can implant up to two embryos. However, in order to reduce the risk of pregnancy complications and premature birth caused by multiple births, Taiwan's artificial reproductive law recommends implanting only one embryo (even one embryo may become identical twins), so choosing the "right" embryo is even more important.

We will score IVF embryos based on two criteria: embryo development speed and appearance. The highest grade is AA, and the implantation rate of grades A and B is usually over 60%. However, it is worth noting that even the highest-grade embryos may still have the risk of chromosomal abnormalities, and conversely, lower-grade embryos may have a chance of successfully implanting and giving birth to healthy babies. In order to reduce the trouble caused by miscarriage, the second check is to confirm whether the chromosomes of the embryo are normal.

C-grade embryos still have potential

In the past, the method of examining embryo chromosomes was to perform an invasive preimplantation chromosome screening (PGT-A) test, which involved slicing the ectoderm cells of the blastocyst for testing to confirm the chromosome status and select embryos with normal chromosomes for implantation. Since sectioning will reduce the number of embryonic cells, theoretically, it will not affect the implantation rate of embryos with good quality, but it may affect embryos that are on the edge of passing. Therefore, A and B grade embryos are generally sent for inspection, and C grade embryos are not suitable for sectioning. However, in this way, embryos that are grade C but have the potential to be fertilized are eliminated, which seems unfair.

Fortunately, with the continuous advancement of technology, there is now a non-invasive preimplantation chromosome screening (Embrace) that can find a way out for C-grade embryos that are not suitable for sectioning. Simply extract the embryo's culture medium to check the chromosome number through the free DNA fragments released from the embryo. This will not affect the cell number of the blastocyst at all, so there is no need to worry about the possible impact on the pregnancy rate.

Many infertile patients suffer from the inability to collect good-quality embryos, and often have to face the dilemma of giving up or taking the risk of implantation. Now, by checking chromosomes through culture medium, normal embryos can be selected for implantation, giving lower-quality embryos the opportunity to be implanted and implanted.

Ask first if they offer inspections

After years of research, the consistency rate of Embrace and PGT-A has become consistent. Compared with PGT-A, which uses local placental cell extraction for testing, Embrace, which uses culture medium for testing, can more comprehensively reflect the status of chromosomes. Although it is still an auxiliary test, it is expected to replace PGT-A in the future.

To avoid affecting accuracy, the first priority is to prevent the specimen from being contaminated. Laboratories engaged in Embrace testing must strictly abide by molecular operating guidelines, and all culture vessels must be sterile and free of residual DNA. In addition, Embrace's unique feature is that any laboratory can provide the same testing quality as long as the standard testing procedures are followed.

However, not all reproductive institutions currently provide Embrace. Considering that the specimen comes from the culture medium that has been with the embryo all the way, couples who are planning to have a baby are reminded to confirm in advance whether the reproductive institution they are visiting provides this test, so as not to miss the opportunity for the test.

Case study of using Embrace to check pregnancy

Not all embryos are suitable for PGT-A before implantation. However, those embryos with scores of only 60 or 70 have a chance to implant and develop into babies in their parents' arms as long as their chromosomes are normal. Especially under the current trend of late marriage and late childbearing, many women encounter the situation of rapid decline in ovarian function between the ages of 35 and 40. Even if they do in vitro fertilization, the chance of pregnancy is reduced because there are not many eggs that can be retrieved. Therefore, every embryo is precious, and Embrace provides a new opportunity to pick out these embryos with potential and not give up any possibility!

A pregnant mother in her 70s came to the hospital for artificial insemination in 2018 and luckily became pregnant with twins. Because she originally planned to have only one baby, the mother went to another hospital for a fetal reduction surgery, but the remaining fetus became infected and died.

In 2020, the pregnant mother came to Qi Xin Obstetrics and Gynecology again for in vitro fertilization treatment. When she checked the AMH, the value was only over 2 points, which meant that the egg inventory had sounded the alarm. Only 6 eggs were retrieved during the first egg retrieval, and only 1 developed into a blastocyst, and its quality was not high. After implantation, the mother experienced abnormal bleeding and the procedure ended in failure. It turned out to be endometrial hyperplasia, so the IVF treatment was suspended and treatment was initiated first.

Rest for a while and then retrieve the eggs again. This time, we retrieved 8 embryos, 2 of which were of better quality, but only grade B to C. We were worried that the embryo section would be affected, so we used Embrace to check the chromosomes and confirmed that only 1 could be kept. Considering that the mother's ovarian response was getting worse and worse and it might be difficult to retrieve eggs again, it was decided to implant this only embryo. Fortunately, it was this embryo that finally allowed the expectant mother to fulfill her wish of having a child.

As we all know, in the IVF process, in addition to having good embryos, a good environment is also required to increase the implantation rate and live birth rate. "Environment" refers to the uterus and endometrium. By collecting endometrial samples at one time, endometrial receptivity test (ERA) can be performed to determine the optimal implantation time; endometrial flora test (EMMA) can be used to determine the bacterial composition of the endometrium; and chronic endometritis infective test (ALICE) can confirm whether there is chronic endometritis and prescribe the right medicine. We believe that by using technology to treat the uterine environment and embryos in a two-pronged approach, it will bring new hope of implantation to couples who are planning to have a baby.