Maternal serum 25-hydroxyvitamin D and C-reactive protein levels in pregnancies complicated with threatened preterm labour

Objective and methods: To measure 25-hydroxyvitamin D [25(OH)D] and C-reactive protein (CRP) serum levels in singleton gestations complicated with threatened preterm labour (TPL, n =59) and compare to normal controls matched for gestational age (n =64). Cases were treated after blood sample according to institutional protocol. Also, analyte levels were compared among cases according to the outcome. Results: Mean serum 25(OH)D levels were similar between cases and controls, with median white blood cell count and CRP levels found significantly higher in TPL cases. Women with TPL delivering preterm displayed shorter mean cervical lengths along with higher CRP and lower 25(OH)D serum levels when compared to those delivering at term. Two multiple linear regression models were constructed to analyse factors related to gestational age at delivery (pooled analysis and only those with TPL). In both models, gestational age positively correlated to cervical length and inversely to CRP levels; whereas, in the TPL model, only 25(OH)D levels correlated positively. Conclusion: Women complicated with TPL showed similar serum 25(OH)D yet higher CRP levels as compared to controls. TPL cases delivering preterm displayed lower 25(OH)D and higher CRP correlated levels.