Utilization of Fertility Treatment in Japan During the First Year of Insurance Coverage: Analysis of Real-World Health Claims Data.

Purpose: In April 2022, fertility treatments, including assisted reproductive technology (ART), became eligible for public health insurance coverage in Japan. This study describes the prevalence and characteristics of infertility diagnoses and fertility treatments during the first year of coverage. Methods: This study analyzed claims data from 14 health insurance associations from April 2022 to March 2023. Infertility diagnoses and fertility treatments, and related comorbidities were identified via diagnosis, procedure, and drug codes. Results: Among 590,006 women and 619,551 men, the highest prevalence of infertility was seen in women (3.9%) and men (0.5%) aged 30-34 years. General fertility treatment was more common among younger women but decreased with age, while ART became more prevalent after age 35. The major prescriptions were hormone preparations for ART and luteal insufficiency among women. The diagnosis ratio of OHSS was higher than previously reported, with 8.0% to 9.6% of women undergoing fertility treatment, particularly receiving ART and younger. Male prevalence of diagnosis and treatment remained low, with multiple factors underlying access to treatment. Conclusions: Public insurance coverage improved access to fertility treatment and enhanced data standardization in Japan. This study indicates the need for targeted strategies to broaden equity in reproductive health services.