Efficacy, safety, and trends in assisted reproductive technology in Japan-analysis of four-year data from the national registry system

Abstract

Purpose This study aimed to evaluate the efficacy, safety, and trends in assisted reproductive technology (ART) in Japan. Methods Data pertaining to treatment cycles, pregnancy rate, live birth rate, age distribution, single embryo transfer rate, and multiple pregnancy rate were analyzed for patients registered in the national ART registry system of Japan from 2007 to 2010. Results The total number of treatment cycles was 161,164, 190,613, 213,800, and 242,161 in 2007, 2008, 2009, and 2010, respectively. The number of ART treatments administered to patients aged ≥40 years was 31.2 %, 32.1 %, 33.4 %, and 35.7 %, respectively, showing an increasing trend from 2007 to 2010. In each of these years, the total pregnancy rate per embryo transfer was 24.4 %, 21.9 %, 22.3 %, and 21.9 % for fresh cycles, respectively, and 32.0 %, 32.1 %, 32.5 %, and 33.7 % for frozen cycles, respectively. The single embryo transfer rate was 49.9 %, 63.6 %, 70.6 %, and 73.0 %, respectively, showing an increasing trend, while the multiple pregnancy rate was 11.5 %, 6.8 %, 5.3 %, and 4.8 %, respectively, showing a decreasing trend. Conclusions From 2007 to 2010 in Japan, the number of ART treatment cycles, number of elderly patients treated, and the single embryo transfer rate increased, while the multiple pregnancy rate decreased. However, the overall pregnancy rate remained stable during the study period.

Oocyte aging underlies female reproductive aging: biological mechanisms and therapeutic strategies

“…Large-scale data obtained from patient records in the Japanese national ART registry show an increase in the treatment cycles of patients aged C40 years. These data show that the percentage of treatment cycles administered to patients aged C40 years was 31.2, 32.1, 33.4, and 35.7 %, respectively, from 2007 to 2010 [5]. Decreases in pregnancy rate per embryo transfer and increases in miscarriage rate were significantly correlated with maternal age and resulted in very low live birth rates in advanced-age women.…”

“…It is widely known that aging reduces fecundity and reproductive capacity in women [1][2][3]. The incidence of aging-related female infertility has increased in industrialized countries, including Japan [4][5][6]. Increasing women's higher education and social advancement are common in these countries.…”

Assisted reproductive technology in Japan: A summary report for 2016 by the Ethics Committee of the Japan Society of Obstetrics and Gynecology

“…In 2008, JSOG recommended restricting the number of ETs to one in order to prevent multiple pregnancies, although double ET was allowed for women over 35 years of age or for women who experienced recurrent implantation failure. As a result, the rate of single ET dramatically increased from 49.9% in 2007 to 73.0% in 2010 and continues to rise (82.7% in FET cycles in 2016). The single ET policy has been credited with improving other indicators of perinatal outcomes in Japan …”

Assisted reproductive technology in Japan: a summary report for 2015 by The Ethics Committee of The Japan Society of Obstetrics and Gynecology

“…In 2008, JSOG recommended restricting the number of ETs to one in order to prevent multiple pregnancies but double ET was allowed for women who are older than 35 years of age or for women who have experienced recurrent implantation failure. As a result, the number of single ETs has increased from 49.9% in 2007 to 73.0% in 2010, while multiple pregnancies have decreased from 11.5% in 2007 to 4.8% in 2010 . The single ET policy has been credited with improving other indicators of perinatal outcomes in Japan …”