High prevalence of vitamin D deficiency in newborn infants of high-risk mothers.

OBJECTIVE

To determine the prevalence of vitamin D deficiency in newborn infants of mothers at risk of vitamin D deficiency because of dark skin or the wearing of concealing clothes (such as a veil) compared with a group presumed not to be at risk. A second aim was to correlate these newborn infants' vitamin D concentrations with biochemical parameters of vitamin D metabolism and bone turnover at birth.

DESIGN

A prospective study conducted between April 2004 and February 2006 including women delivering during this period and their newborn infants.

SETTING

The outpatient clinic of the obstetrics department, Sint Franciscus Gasthuis, Rotterdam, the Netherlands.

PATIENTS

Eighty seven newborn infants of healthy mothers with either dark skin and/or concealing clothing (risk group) or light skin (control group).

RESULTS

We found a significant difference in the prevalence of vitamin D deficiency (25-hydroxyvitamin D(3) <25 nmol/l) between newborn infants of mothers at risk and those of mothers in the control group (63.3% vs 15.8%; p<0.001). Mean alkaline phosphatase concentrations were significantly higher in the at risk group.

CONCLUSIONS

Newborn infants of mothers with dark skin or wearing concealing clothes are at great risk of vitamin D deficiency at birth. The clinical implications are unknown. Further research is necessary to determine the long-term consequences of maternal and neonatal vitamin D deficiency so that guidelines on vitamin D supplementation during pregnancy can be issued.