Ms. S came to the clinic for the purpose of a second child. After a preliminary examination, she learned that her AMH was only 0.6 ng/mL. Although both fallopian tubes were unblocked and her husband’s sperm quality was also good, she decided to go through the IVF treatment. She was 39 years old, and it is estimated that an average of 0 to 2 eggs can be retrieved each time. After discussion, we decided to do embryo collection with PGS and secondary egg retrieval to collect an euploid embryo or 4-5 non-biopsy embryos first, then do embryo transfer. However, in several egg retrievals, the embryos were all BC grades and could not be biopsied. We finally went through three months and five times of egg retrievals, obtained 15 eggs and 5 embryos, and started the embryo transfer process (Table 1). Due to the difficulty of obtaining the embryos, all the recommended examinations were done before transfer, including immune check, hysteroscopy, hormones and endometrial receptivity analysis (ERA). Although the five embryos are all BC grades, fortunately, four of them were formed on the fifth day and only one was formed on the sixth day, and the shape is also good. After discussion, we decided to divide the embryos into two groups, and the first two embryos with better shape were transferred first. Fortunately, Ms. S became pregnant at the first implantation, and finally gave birth to a baby at 37 weeks of pregnancy.

Table1. Egg retrieval of Ms. S

Another Ms. Q was not so lucky. She was 42 years old when she first visited the clinic. Her AMH was 0.56 ng/ml. After four egg retrievals in two months, we obtained a total of 11 eggs and derived 4 embryos, one of which could even be biopsied. However, to our disappointment, the result of the embryo was abnormal chromosomes (Table 2). Maybe Ms. Q was tired of undergoing the treatment, and Ms. Q suggested to me that she wanted to go through the embryo transfer. I think about it carefully. According to the artificial reproductive law, only a maximum of 4 embryos can be implanted at a time. There are 3 embryos so we considered moving on to  transfer. We also made all the above preparations. In addition, because Ms. Q had failed in her previous IVF treatment, and her immune indicators were abnormal, she was referred to an immunologist, hoping to minimize the variables of transfer. However, this transfer was the result of failure. Although it failed, Ms. Q still bravely started to retrieve eggs again. However, in the next several times of egg retrieval, only 0 or 1 egg can be retrieved, and the abnormal  rate of the eggs also increased significantly. After 6 rounds of egg retrievals, we only obtained one BC embryo on the seventh day, which has not been implanted yet (Table three).

Table2. Egg retrieval of Ms. Q (Before first transfer)

Table3. Egg retrieval of Ms. Q (After first transfer)

This seems to be the daily life of a Stork Fertility Center. In the group whose ovarian function has declined, those who are less than 38 years old are suggested to do egg collection and those who are more than 38 years are suggested to do embryo collection. In recent years, the increasing number of data on thawing eggs of women in advanced maternal age, advancing biopsy technology, and IVF subsidies make us think about the meaning of egg collection and embryo collection. We should consider changing strategies to obtain the greatest benefits, and reduce unnecessary waste while ensuring the pregnancy rate.

It is undeniable that the group that most needs to consider egg or embryo collection is that the ovarian reserve has almost bottomed out (<0.8ng/mL), especially when combined with advanced age or irregular menstruation. We have to avoid the experience of Ms. Q- No more eggs can be retrieved after transfer.

In addition to the above-mentioned purposes, another purpose of egg collection is to save the cost of fertilization and embryo culture. We want to obtain at least one chromosomally normal embryo based on the normal rate of eggs, so we will do egg collection according to the number of eggs needed for each group of age. As for embryo collection, Under the condition of advanced maternal age and no IVF subsidy, one of the important purposes is to increase the number of embryo implants according to age. We want to increase the probability of having an embryo with normal chromosomes at the time of implantation and improve the success rate of implantation in the case of advanced maternal age. However, after the IVF subsidy implementation, at most two embryos can be implanted at a time. The purpose and goal of embryo collection must be rethought.

The first question we have to think about is- how much is an embryo? I think that if you are under 38 years old, you can still consider egg collection with at least one chromosomally normal embryo as the goal. What I want to discuss here is whether there is a chance for the elderly group to consider egg collection to save the cost of fertilization and embryo culture, since we have more and more data on thawing eggs of older ages. The following is the statistics of Stork Fertility Center laboratory in the past two years (Table 4)

Table 4. Blastocysts derived rate of fresh eggs vs. thawed eggs (from MII)

Without considering the cost of medicine, a course of egg freezing treatment is TWD 64000, and a course of IVF treatment is TWD 133500. The following lists the expected cost of ages 38-40 years old and older than 40 years old for egg collection once plus embryo collection once or two times of embryo collection, both with subsidies. (Table 5)

Table 5. A roughly estimated price of embryos (Includes secondary egg retrieval)

* This table is calculated according to the 2022 price list.

Another problem is that with the current subsidy policy, at most two embryos can be transferred at one time. It is actually quite unfavorable for the elderly group. Especially for those over 40 years old, the normal chromosome rate of embryos is about 20% or less. Without PGS, the uncertainty of embryo chromosome status is extremely high. Is it worth considering a biopsy of a BC grade embryo? The following table shows the pregnancy rate statistics of transfer of non-biopsied embryos and transfer of only one biopsied BC grade embryo (Table 6):

According to table 6, my personal interpretation is that when the AMH is low (<0.8ng/mL), the 38-40-year-old group can also consider an egg collection strategy to save the cost of fertilization; as for the group over 40, according to our data, it seems that the result of egg collection can be good too. However, under the condition of a small number and uncertainty of thawing eggs, we have to be conservative in the strategy. As for whether BC embryos should be biopsied, the current sample size is still relatively small, but in the case of people over 40 years old, the transfer of a BC biopsied embryo can greatly improve the pregnancy rate compared with the transfer of two non-biopsied embryos. This group over 40 years old is worthy considering BC grade biopsied.