The Japan Society of Obstetrics and Gynecology (Japan) has continued clinical research to investigate whether the “pre-implantation test”, which examines all the chromosomes of fertilized eggs fertilized in vitro and returns only those that are normal to the mother’s womb, is effective for infertility treatment. The maternity) announced the interim results on the 23rd. The birth rate of all subjects was only 17%, but if fertilized eggs could be transplanted into the uterus, the miscarriage rate would decrease and the pregnancy rate tended to improve. “We will continue to carefully consider whether the test is beneficial,” said the Nissan woman.
Published at a symposium held online. At medical institutions nationwide certified by Nissan women, I was fertilized in vitro but could not get pregnant more than once I experienced miscarriage more than once One of the couples has a chromosomal structural abnormality-For couple Approximately 4,300 women in their 30s and 40s who were examined were analyzed. According to Nissan women, the pregnancy rate of women who could transplant fertilized eggs into the uterus was 66%, and the miscarriage rate was 10%. Infertility treatment results of medical institutions registered by Nissan women in 2019 are 35% pregnancy rate and 25% miscarriage rate.
Although the simple comparison is not possible, the test was evaluated as “useful” as a fertility treatment only when fertilized eggs could be transplanted. On the other hand, 60% of women could not find fertilized eggs with no abnormalities in the number of chromosomes and could not transplant them into the uterus. For this reason, the birth rate was 17% for all the women who were tested. The birth rate for general in vitro fertilization without pre-implantation inspection was about 20%, and no improvement was seen. It is thought that the factors are that the rate of abnormalities in fertilized eggs increases with aging and that some of the fertilized eggs are damaged during the test.
Akira Kuwahara, director of Ladies Clinic Cosmos, who is in charge of data, evaluated that “60% could not be transplanted, but we were able to avoid transplantation that could not be expected to become pregnant”, but the overall birth rate did not improve. “It is necessary to verify whether it will be beneficial to the couple,” he said. In the future, it is said that analysis by age and facility will be promoted. Pre-implantation tests usually look for excess or deficiency in the number of chromosomes, 23 vs. 46. It is used overseas for the purpose of preventing miscarriage, and the Japanese Society of Reproductive Medicine says that it is “recommended” for women who have miscarriage twice in a row when it is used for the purpose of avoiding miscarriage.
The Ministry of Health, Labor and Welfare are discussing whether pre-implantation examinations for the purpose of infertility treatment for women with repeated miscarriages should be included in the scope of public medical insurance at the Central Social Insurance Medical Council, an advisory body to the Minister of Health, Labor and Welfare. On the other hand, Nissan women have not accepted the guidelines because of concerns that it may lead to the elimination of fertilized eggs that can be born, such as Down’s syndrome, which has one more chromosome 21 and Turner’s syndrome, which has one less sex chromosome.
Symposium These ethical issues were also discussed at Mu. Koji Kugu, director of the Department of Obstetrics and Gynecology, Sumida Hospital, Tokyo Metropolitan Bokuto Hospital, said, “It is a technology that leads to avoiding miscarriage, and at the same time, it also leads to the elimination of persons with disabilities. It is necessary to repeat the discussions. ” On the other hand, women suffering from miscarriage and infertility complained, “I want you to be able to use tests to avoid miscarriage.”