The Influence of Prenatal Vitamin D Supplementation on Dental Caries in Infants

Objectives Early childhood caries (ECC) originates prenatally. This study investigated whether a relation exists between levels of vitamin D in the umbilical cord and caries in offspring. Methods A prospective cohort of expectant mothers was selected from a high-risk urban population receiving prenatal care in Winnipeg, Canada. Participants self-selected into 1 of 2 groups. The intervention group received 2 oral prenatal doses of 50 000 international units (IU) of vitamin D in addition to routine prenatal care. The control group received routine prenatal care. A prenatal questionnaire was completed at the first visit. Umbilical cord blood was analyzed for 25 hydroxyvitamin D (25(OH)D). At the time of their infant's first birthday, participants returned for a follow-up questionnaire and a dental examination of the infant. A p value ≤ 0.05 was significant. Results In all, 283 women were recruited (mean age 23.4 ± 5.6 years), 141 in the intervention group and 142 in the control group. The mean cord 25(OH)D level was 49.6 ± 24.3 nmol/L and did not differ between the groups. For the follow-up visit, 175 women returned. Overall, 26.3% of infants had ECC, and the mean decayed tooth (dt) score was 0.94 ± 2.16 teeth (range 0-16). There was no significant difference in prevalence of ECC between the intervention and control groups (p = 0.21). Poisson regression determined an inverse relation between 25(OH)D levels and dt scores (p = 0.001). Socioeconomic factor index (SEFI), age and enamel hypoplasia, but not vitamin D supplementation were significantly and independently associated with dt. Multiple logistic regression models also revealed that higher SEFI score, age and enamel hypoplasia were associated with ECC. Conclusion No relation was found between the 2 groups and prevalence of ECC. However, significance was seen in an inverse relation between 25(OH)D levels and the number of decayed primary teeth. Further studies with higher levels of vitamin D supplementation are needed.