Vitamin-D deficiency during pregnancy leads to problems with neurological development in infants

Hypovitaminosis D, or a lack of vitamin D in the organism, is a health problem the world over. It is particularly worrying when pregnant women lack this vitamin because it can have a direct effect on the neurological development of their children. A longitudinal study by the research group Nutrition and Mental Health (NUTRISAM) has monitored almost 800 health women during pregnancy to determine their levels of vitamin D, what factors predispose to having a deficiency and how this affects the birth and development of infants. The data obtained show that more than half of the women studied have vitamin-D deficiency and reveal what factors cause women to suffer from this deficiency.

These results, which have been published in the journals Scientific Reports and Nutrients, are part of the study ECLIPSES, in which more than 800 healthy pregnant women from Tarragonès and Baix Camp took part. According to the research team, the results obtained can be extrapolated to the whole Mediterranean basin. One of the main novelties of the work with respect to previous research is the multifactorial approach because it measures not only the nutritional status of the mother but also such other aspects as the mother’s genetic markers, emotional state and environmental pollutants during pregnancy.

The study evaluated several of the mother’s sociodemographic, obstetric, anthropometric, lifestyle and nutritional variables and blood samples during pregnancy, and the state of the infant after birth. It also evaluated the levels of environmental pollution around the women’s homes. The results indicate that more than half of the participants (50.2%) had vitamin-D deficiency and 30.3% insufficiency. This lack was detected above all in Arabian women and in women with dark skin – which is more resistant to the synthesis of vitamin D from the sun –, who are obese, lead a sedentary lifestyle or have a low socioeconomic level.

“Although the region is a sunny one, the latitude of the Mediterranean basin is not the best for synthesising vitamin D,” says Victòria Arija, one of the researchers who directed the study. She also points out that the levels of this vitamin “vary considerably as a function of whether the pregnancy is during the winter or the summer.”

The research also revealed that deficiency during pregnancy has a negative impact on the neurological development of infants after birth. The research group studied the first 40 days of life: reaction to sound and light, the time and type of reaction, etc. “The tests that measure the levels of development showed that mothers with vitamin-D deficiency have children with worse cognitive levels, motor skills and capacity for language,” says Dr Arija.

These results have prompted the research group to make preventive recommendations such as “giving a supplement to pregnant women with most risk factors, now that we know what they are.” In the light of the results of this research, the research group suggests taking measures to prevent vitamin-D deficiency. “Prenatal care should include vitamin-D assessments and women should increase their intake of fish, dairy products and fruit during pregnancy.”

Reference: Díaz-López, A., Jardí, C., Villalobos, M., Serrat , N., Basora, J., Arija, V.. Prevalence and risk factors of hypovitaminosis D in pregnant Spanish women. Sci Rep 10, 15757 (2020). https://doi.org/10.1038/s41598-020-71980-1 Voltas, N., Canals, J., Hernández-Martínez, C., Serrat, N., Basora, J., Arija, V. Effect of Vitamin D Status during Pregnancy on Infant Neurodevelopment: The ECLIPSES Study. Nutrients 2020, 12, 3196; doi:10.3390/nu12103196