Comparison of Umbilical Cord Serum Vitamin D Levels between Infants with Transient Tachypnea of the Newborn and those without Respiratory Distress

Transient tachypnea of the newborn (TTN) is one of the most frequent causes of respiratory distress in neonates. A relationship has been shown between vitamin D deficiency and respiratory disorders in neonates. This research was carried out to evaluate the serum level of vitamin D in TTN newborns and their mothers compared to the control group.

This case-control research was conducted during 2016-2019 in a general hospital affiliated with Mashhad University of Medical Sciences, Iran. Thirty-four infants with TTN and 82 neonates in the control group as well as their mothers were investigated. The levels of umbilical cord serum vitamin D in infants with TTN and also their mothers were compared to the control group.

The mean levels of serum vitamin D in infants with TTN and their mothers were 8.11 ± 4.32 and 12.6 ± 10.12 ng/mL, respectively (P<0.001), whereas they were 19.21 ± 12.71 and 25.96 ± 16.6 ng/mL in the newborns of the control group and their mothers, respectively (P<0.001). The mean differences (95% CI) of neonatal and maternal vitamin D level between the two groups were 11.10 (7.92–14.28) and 13.36 (7.90–18.08), respectively. In the TTN group, 100% of the infants had vitamin D levels less than 30 ng/mL (79.4% had severe, 17.6% had moderate and 2.9% showed mild deficiency). However, vitamin D levels lower than 30 ng/mL were observed in 76.4% of the neonates in the control group (28.8% had severe, 31.1% showed moderate and 16.3% had a mild deficiency) (P<0.001).

The serum vitamin D levels of infants with TTN and their mothers were significantly lower than the control group. Therefore, TTN in infants may be reduced through the treatment of vitamin D deficiency in mothers.