Vitamin D, muscle strength, prolonged labour, Caesarean sections and lifestyle : Clinical and intervention studies in pregnant Somali and Swedish women and new mothers

Sammanfattning: Long-term severe vitamin D deficiency may cause osteomalacia with muscle weakness, pain, soft bones, cramps and eventually death. In a pilot study, I found many Somali women to be vitamin D deficient and very weak. This raised my interest and resulted in the research questions regarding if and how this weakness was linked to vitamin D deficiency, if it could be treated with simple lifestyle advice and supplementation, and if pronounced deficiency could cause serious birth outcomes due to prolonged labour?Study I showed that 90% of pregnant Somali women (n = 52) and new mothers from primary antenatal care suffered from vitamin D deficiency with pronounced muscular weakness and signs of skeletal degradation, compared with 10% of the Swedish women (n = 71). Handgrip strength was predicted by vitamin D levels.Study II showed that vitamin D supplementation among those with insufficient levels at baseline reversed deficiency and skeletal degradation. Furthermore, increased strength in hands and legs was predicted by the amount of supplement intake.Study III aimed to investigate the vitamin D levels and the birth outcomes of cesarean sections and assisted birth for prolonged labour. A directed acyclic graph was established to adjust for covariates. A causal effect of critically low (unmeasurable) vitamin D levels on the outcomes of caesarean sections, emergency caesarean sections and assisted birth for prolonged labour was found with the increased odds of four, nine and six times to one for the birth outcomes, respectively.Lifestyle associated with vitamin D may concern many due to risk of low sun exposure, for example, when working long office hours, engaging in excessive computer gaming, using sunscreen, wearing veiled clothes, or when having special diets like vegan food.It is important to monitor individuals in primary- and antenatal care with muscle weakness and risk factors for vitamin D deficiency, especially in the high-risk group of Somali pregnant women and new mothers.