TOKYO, June 14 — Multiple pregnancies resulting from assisted reproductive technology in Japan reached a record 4,354 cases in 2023, a year after the treatment became eligible for public health insurance coverage.
Kyodo News reported that the figure was up 36 per cent from 2022, with researchers saying the rise may reflect an increase in patients choosing to transfer multiple embryos in hopes of completing treatment within the limited number of cycles covered by insurance.
Multiple pregnancies, such as twins and triplets, carry higher risks for pregnant women. The Japan Society of Obstetrics and Gynaecology recommends, in principle, that only one embryo be transferred at a time.
The country's public insurance system covers embryo transfers up to six times for women who were under 40 when they began fertility treatment and up to three times for those aged 40 to 42.
"The insurance system needs to be reviewed, taking into account the potential burden of high-risk pregnancies on perinatal care," said Toho University lecturer Ayumu Ito, whose institution was involved in the study.
During in vitro fertilisation, multiple embryos may be transferred at one time to increase the chance of pregnancy, raising the likelihood of multiple pregnancies. The rate of such pregnancies exceeded 10 per cent through 2007.
In 2008, the society recommended single embryo transfer in principle. It said that two embryos may be transferred for women aged 35 or older and those who had failed to become pregnant after two or more transfers.
The multiple pregnancy rate subsequently declined, remaining at around three per cent from 2014 onward. According to the study's analysis of the society's database, it rose to 3.8 per cent in 2023, the year after public insurance coverage was expanded to fertility treatment.
Most of the cases involved twins, while there were 69 cases of triplets and six cases of quadruplets.
The total number of assisted reproductive technology procedures also rose. Furthermore, the researchers found that transfers of two or more embryos increased, particularly among people aged 41 or older.
