Association between umbilical cord vitamin D levels and adverse neonatal outcomes.

OBJECTIVE

We investigated the associations between cord blood concentration of 25-hydroxyvitamin D [25(OH)D], neonatal outcomes, and the risk of hospitalization during the first year of life.

METHODS

A total of 402 newborn infants and their mothers were prospectively enrolled and divided in four groups according to season of the year. We determined 25(OH)D serum concentrations from maternal-neonatal pairs at delivery by electrochemiluminescence immunoassay. Cut-offs at 25, 50, and 75 nmol/L defined vitamin D status, corresponding to deficiency, insufficiency, and sufficiency, respectively. Crude odds ratio (cOR) and 95% confidence intervals (CI) were estimated using logistic regression.

RESULTS

Vitamin D severe deficiency (i.e., <25 nmol/L) was present in 18% of newborns. Cord blood severe deficiency was associated with an increased risk of preterm birth (cOR 3.6, 95% CI: 1.1-12.2), neonatal respiratory distress syndrome (cOR 5.9, 95% CI: 1.1-33.2), and increased risk of hospitalization during the first year of life because of acute respiratory infection (cOR 3.9, 95% CI: 1.4-10.6) or acute gastroenterocolitis (cOR 5.2, 95% CI: 1.4-19.1).

CONCLUSION

Cord blood vitamin D deficiency is associated with increased risk of preterm birth, neonatal respiratory distress syndrome, and hospitalization during the first year of life.