Influence of Maternal Prenatal Vitamin D Status on Infant Oral Health

70 years (66.9 nmol/L) than what is reported in this longitudinal cohort investigation. 20 In
general, vitamin D deficiency appears to be a growing concern among pregnant women
in Canada as the ability to endogenously produce vitamin D is restricted to only a few
months during the summer. The need for vitamin D supplementation is quite apparent. In
addition, these participants may have future increased risk for other chronic health
conditions. 21
Many participants exhibited vitamin D levels consistent with vitamin D
deficiency, depending on the different thresholds proposed. A recent recommendation to
adopt values < 80 nmol/L as evidence <strong>of</strong> vitamin D deficieny is based on the inverse
relationship between 25(OH)D and parathyroid hormone (PTH) levels; the threshold
where PTH levels begin to plateau. When this threshold was applied to our participants,
90% were found to have deficient concentrations. This is somewhat alarming given the
fact that the developing fetus is entirely dependent on maternal vitamin D concentrations.
However, even when the different thresholds for deficiency that appeared in Chapter 3
were applied there were still a considerable proportion <strong>of</strong> participants that had levels in
the deficient range; 46.5% (≤ 40 nmol/L) and 35.0% (≤ 35 nmol/L).
Questionnaire responses relating to milk consumption were encouraging since it is
vitamin D fortified. Half <strong>of</strong> those women recruited into this study were consuming milk
on a daily basis while another one-third was drinking milk a few times per week. This is a
positive sign considering concerns over possible lactose intolerance in some Aboriginal
populations. Milk is a good source <strong>of</strong> vitamin D for women residing in urban centres,
where milk is generally affordable compared with extreme prices in the northern regions
<strong>of</strong> Canada. 22 Apart from dietary supplements, milk use may be a good means <strong>of</strong> obtaining
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