Observational study of vitamin D levels and pain in pregnant immigrant women living in Sweden

The aim was to determine the prevalence of vitamin D insufficiency in pregnant immigrant women assessed by the levels of 25-hydroxyvitamin D, parathyroid hormone (PTH) and alkaline phosphatase (ALP) as well as the correlation to musculoskeletal pain. Sixty-eight pregnant immigrant women were included. Fifty-one native Swedish pregnant women served as controls. 25-hydroxyvitamin D, PTH, ALP and musculoskeletal pain, rated on a visual analogue scale, were analyzed in all women in gestational week 12 and in the immigrant women at 6-12 months postpartum. A significantly higher proportion of immigrant women (77.9%) had levels of 25-hydroxyvitamin D <25 nmol/l compared with 3.9% in controls. Of the immigrant women, 29.4% had 25-hydroxyvitamin D levels <12 nmol/l, but none of the controls. Musculoskeletal pain evaluated with a visual analogue scale WAS) was significantly higher for the immigrant women than for the controls at gestational week 12. However, no within group correlation was seen between 25-hydroxyvitamin D levels, PTH or ALP and pain. A significant negative correlation between changes in 25-hydroxyvitamin D and pain from gestational week 12 to postpartum was observed. Hypovitaminosis D is prevalent in immigrant women living in Sweden. There is an indication that pain might be associated with hypovitaminosis D.