Establishment and application of criteria for the elective transfer of two good-quality embryos to reduce high-order multiple pregnancies

This study was carried out to establish criteria for the elective transfer of two good-quality embryos to reduce high-order multiple pregnancy rates. The pregnancy and multiple pregnancy rates per transfer were retrospectively analyzed in 128in vitro fertilization and embryo transfer (IVF-ET) cycles. The analysis revealed that the pregnancy and multiple pregnancy rates were 26.6% (34 of 128) and 23.5% (eight of 34), respectively. Five twin and three triplet pregnancies were included. The pregnancy rates in women 29 years old and younger, 30–34 years, 35–39 years, and 40 years and older were 21.2 (seven of 33), 37.0 (17 of 46), 25.8 (eight of 31), and 11.1% (two of 18), respectively. There was a significant difference of the pregnancy rates between 30 and 34-year-old and 40-year-old and older women (P < 0.05). The multiple-pregnancy rate in women 40 years and older was 0%. Three triplet pregnancies were established only in the first attempt of IVF-ET. The pregnancy rates in women, to whom good-quality embryos (0–4) were transferred, were 0% (none of 12) for 0, 17.2% (five of 29) for one, 41.2% (seven of 17) for two, 30.8% (12 of 39) for three, and 32.3% (10 of 31) for four and more embryos, respectively. The multiple pregnancy rates in women who had good-quality embryos of one, two, three, and four and more transferred were 0% (none of five), 23.5% (four of seven), 16.7% (two of 12), and 20.0% (two of 10), respectively. The criteria for the elective transfer of two good-quality embryos were established as follows: age < 40 years, a first treatment cycle, and more than three good-quality embryos available for transfer. After the application of the established criteria, the overall pregnancy and multiple pregnancy rates were 30.4% (14 of 46) and 14.3% (two of 14), respectively, which was satisfactory as compared with those in the 128 IVF-ET cycles before application of the criteria. An elective transfer of two good-quality embryos can be highly recommended to avoid high-order multiple pregnancies in subjects with the established criteria.