Prevalence of infant and maternal anemia during the lactation period in Japan

BACKGROUND: The perinatal period is associated with a high risk of infant anemia. The aim of the present study was to determine the prevalence of infant and maternal anemia during the late lactation period and the risk factors for anemia in Japan. METHODS: This retrospective cohort study was based on data from health checkups of healthy infants at 6-7 and 9-10 months of age and their mothers who visited Akitsu Children's Clinic between September 2013 and August 2015. Complete blood count data from infant blood samples obtained at 6-7 months and 9-10 months and from maternal blood samples obtained at 6-7 months, information on feeding methods, and other related parameters were analyzed. RESULTS: Data from 388 mother-infant pairs were analyzed. The prevalence of infant anemia was 21.1% at 6-7 months and 29.1% at 9-10 months. The prevalence of anemia in exclusively breast-fed infants was 28.4% at 6-7 months and 40.0% at 9-10 months. The risk factors for infant anemia at 9-10 months were exclusive breast-feeding, lower gestational age at birth, male sex, and high weight gain. The prevalence of maternal anemia was 10.5%. There was no correlation between infant and maternal hemoglobin in exclusively breast-fed infants. CONCLUSIONS: Japanese infants who were breast-fed exclusively had a high prevalence of anemia. A nationwide strategy to prevent anemia is required to prevent infant anemia, even in a nutrition-rich country such as Japan.