Nationwide survey of cryostorage tank management for fertility preservation in Japan.

purposeThe aim of this study was to investigate cryostorage tank management practices in Japan at the time of the survey and to identify challenges to establishing a system for long-term safe storage of fertility preservation specimens.

methodsEmbryologists from 622 institutions registered for in vitro fertilization and embryo transfer with the Japan Society of Obstetrics and Gynecology were surveyed online about their practice of cryostorage tank management.

resultsThe response rate was 56.6%. In 92.1% of facilities, the remaining liquid nitrogen status in the tank was monitored once per week or more frequently, with the longest reported monitoring interval being once per month. Monitoring methods for liquid nitrogen levels were liquid level measurements (72.2%), tank weight (5.1%), both methods (10.5%), and refilling at predetermined intervals without checking the remaining liquid nitrogen level (12.2%). Only 9.7% of facilities had alarm systems installed on the tanks. Procedures for responding to tank failure were established in 45.2% of facilities. Most of these measures addressed compensation or patient consent, and only 30.4% of facilities had considered responses specifically aimed at preventing specimen loss in the event of tank failure.

conclusionThis nationwide baseline survey suggests that, at the time of the survey, routine monitoring of liquid nitrogen levels was widely practiced in Japan. In contrast, preparedness for rapid liquid nitrogen loss due to vacuum insulation failure of the tanks was limited, particularly in terms of alarm systems and specific response measures. To address these issues, the development of detailed guidelines and standardized operational procedures for cryostorage tank management is considered necessary.