Women who have low vitamin D levels during pregnancy are more likely to have babies who develop tooth enamel problems, which can lead to tooth decay, new Canadian research says.

Researchers from the University of Manitoba examined data from 135 babies between the ages of seven and 16 months. They found that 21.6 per cent of them had tooth enamel defects and 33.6 per cent had early childhood tooth decay.

Mothers of children with tooth decay had significantly lower vitamin D levels than mothers of children with healthy teeth.

As well, mothers of children who had enamel problems had slightly lower vitamin D levels during pregnancy than mothers of children without enamel problems.

The researchers found that having enamel defects significantly increased the risk of developing tooth decay.

The findings were presented Friday at the General Session of the International Association for Dental Research in Toronto.

For their study, the researchers analyzed data from pregnant women in their second trimester. Only 10 per cent of them were deemed to have adequate levels of vitamin D, which is defined as 80 nanomoles per litre.

The mean vitamin D level among the women in the study was between 24.4 and 48.1 nanomoles per litre.

Women in the study who drank more milk and took pre-natal vitamins had higher vitamin D levels.

This is the first study to analyze vitamin D levels during pregnancy and how they might influence a baby's early dental health.

Abstract:

Influence of Maternal Vitamin D Status on Infant Oral Health

R. Schroth, C. Lavelle, and M.E. Moffatt.

Objectives: Inadequate maternal 25(OH)D levels during pregnancy may affect primary tooth calcification predisposing enamel hypoplasia (EH), a risk factor for early-childhood-caries (ECC). The purpose of the study was to determine the 25(OH)D status of expectant mothers, the incidence of EH and ECC among their infants and the relationship between prenatal 25(OH)D levels and both EH and ECC.

Methods: This prospective study recruited participants during pregnancy. A prenatal questionnaire was completed and serum sample drawn for 25(OH)D assay. Infant dental exams were completed at follow-up appointments; EH and ECC were recorded while the parent/caregiver completed a questionnaire. The examiner was blinded to each mother's vitamin D status. EH and ECC were defined by established indices. A p value of ¡Ü 0.05 denoted significance.

Results: 206 women were enrolled during their second trimester. The mean serum 25(OH)D was 48.1 ¡À 24.4 nmol/L. 34.5% had levels ¡Ü 35 nmol/L, a formerly-defined threshold of deficiency. Only 21 women (10.5%) had concentrations ¡Ý 80 nmol/L, denoting adequacy. Vitamin-D concentrations were related to the frequency of milk consumption and prenatal vitamin use (p<.001). 135 infants (55.6% male) were examined at 16.1 ¡À 7.4 months of age. 21.6% had EH while 33.6% had ECC. Mothers of children with EH had lower but not significantly different mean serum 25(OH)D concentrations during pregnancy than those of children without EH (43.2 vs. 51.4 nmol/L, p=.07). However, mothers of children with ECC had significantly lower 25(OH)D levels than those whose children were caries-free (43.9 vs. 52.8 nmol/L, p=.034). Infants with EH were significantly more likely to have ECC (p<.001).

Conclusions: This study shows for the first time that maternal vitamin-D levels may have an influence on the primary dentition and the development of ECC.