Most Pregnant Women and A Half of 1-year-old Children in Japan Have Vitamin D Deficiency: Results from An Inner-City Birth Cohort
Sunday, March 4, 2018
South Hall A2 (Convention Center)
Fumiya Yamaide, Madoka Tomura, Mamoru Sato, Yoichi Suzuki, Fumio Nomura, Naoki Shimojo, MD, PhD

Many studies suggest that Vitamin D insufficiency contribute to allergen sensitization and allergic diseases, but those findings vary between populations. The aims of this study were to evaluate vitamin D levels in pregnant women and infant at birth and 1 year, and to assess association of vitamin D levels with allergic diseases and allergen sensitization in early life.


CHIBA study is a longitudinal birth cohort study of 256 infants with family history of atopy in Chiba city (urban area), Japan. Serum Vitamin D levels in mothers during pregnancy, cord blood, and children at 1 year of age were measured using liquid chromatography tandem mass spectrometry. Associations between vitamin D levels with allergic diseases and allergen sensitization at 1 year of age were analyzed.


Prevalence of atopic dermatitis, food allergy, and bronchial asthma at 1 year of age were 15.6%, 8.3%, and 2.0%, respectively. Sensitization rate to house dust mite and egg white were 7.1% and 33.3%. Median vitamin D levels (ng/ml) in mothers, cord blood, and children were 12.1 (interquartile range: 9.1-16.0), 6.0 (4.6-8.2) and 21.0 (13.7-25.7), respectively. Prevalence of vitamin D deficiency (Vitamin D<20 ng/ml) in mother and 1-year-old children were about 90% and 50%. There was no correlation between vitamin D levels in maternal and cord blood and allergic diseases /allergen sensitization at 1 year of age. Vitamin D levels in 1-year-old children were correlated with egg sensitization.


In Japanese urban area, almost all pregnant women and a half of 1-year-old children have vitamin D deficiency.