Survey on the use of drug therapy for threatened preterm labor in Japan from 2019 to 2021 using the NDB Open Data Japan.

Preterm delivery is associated with perinatal outcomes such as neonatal complications and deaths. Uterine contraction suppressants are administered to treat. In Japan, ritodrine hydrochloride (ritodrine) and magnesium sulfate (magnesium) are covered by insurance. However, ritodrine was withdrawn from the United States market in 2011, and in Europe, its administration was only limited for short-term use in 2013. In this study, we analyzed in the use of ritodrine and magnesium using the NDB Open Data Japan and annual trends in the number of births issued by the Ministry of Health, Labor, and Welfare for 2019-2021. Ritodrine prescribed per birth decreased from 2019 to 2020, while the level 2021 was the same as 2020. Magnesium decreased between 2019 and 2021. The ages were administered ranged from 15-49 years. The results of this study suggest that ritodrine and magnesium are still frequently used in Japan for the treatment of preterm labor. Recently, the American College of Obstetricians and Gynecologists advocated the use of calcium antagonists such as nifedipine as the first choice. We extracted trends in the use of nifedipine, in the target age group for the treatment of imminent preterm labor. The number of nifedipine prescriptions increased every year. However, nifedipine has no indication for the treatment of imminent preterm labor in Japan, it should be noted that this is not accounting for the treatment of impending preterm labor because the prescriptions were classified as vasodilators in the NDB Open Data. [ABSTRACT FROM AUTHOR]