Study: Babies’ Soft Skull Due To Mothers’ Lack Of Vitamin D

Skull-bone softening in newborns may be tied to a vitamin D deficiency in the womb, according to a recent report from Japanese researchers.

Soft skull bones, also known as craniotabes, in normal newborns are usually regarded as no cause for alarm. In a report published in the Journal of Clinical Endocrinology and Metabolism, however, Tohru Yorifuji and colleagues at Kyoto University Hospital dispute this, pointing to evidence that the condition is associated with type 1 diabetes, reduced bone mass during childhood and lowered immunity.

In the study, researchers screened 1,120 normal infants at five to seven days of age. Craniotabes was considered present when the skull bones reversibly bended by application of pressure by the examiner’s fingers.

They found that 246 babies—22 percent—had craniotabes. The highest rate occurred among infants born in April and May, and the lowest in those born in November.

Vitamin D production in the body is triggered by sunlight, and Yorifuji’s team points out that the rate of craniotabes appears to have been influenced by light exposure approximately four months prior to delivery. They say this strongly suggests that the condition is associated with vitamin D deficiency in utero.

The report concludes with the recommendation that breast-fed infants with craniotabes be treated with vitamin D, or—preferably—all pregnant women be treated with vitamin D.