The Utilization of Serum Folate and Homocysteine Tests and the Prevalence of Folate Deficiency in Reproductive-Age Korean Women during the COVID-19 Pandemic

This cross-sectional, laboratory-based study evaluated the utilization of serum folate and homocysteine assays and the prevalence of folate deficiency among Korean women of reproductive age seeking care at local clinics and hospitals during the COVID-19 pandemic. The highest folate deficiency prevalence was found in women aged 20 to 24 years, at 11.2% using a cut-off of <3 ng/mL and 24.9% using <4 ng/mL. Women tested in 2020 and those in Jeolla province, Gyeongsang province, and Jeju Island had higher deficiency risk. An optimal homocysteine cut-off of >8.4 µmol/L was suggested for detecting folate deficiency of <4 ng/mL, lower than the manufacturer's reference interval. The study lacked clinical information such as vitamin B12 status, hematologic parameters, and supplement use. Prevalence findings were consistent with prior Korean studies and public database records.