Procedure 
Inclusion criteria were: admission for delivery and signed informed consent from the mother, and if married also the father, to analyze 25(OH)D and to enter the medical records from both the mother and the newborn. Women were excluded if they did not speak Arabic, English or Urdu. Maternal venous blood was collected together with the routine blood sampling at admission to the labor ward and for the fetus, paired umbilical cord blood samples were collected directly after delivery in  pre-heparinized syringes on unclamped cord. Before discharge, the mothers answered a questionnaire in the presence of research officials regarding education, physical activity, time spent outside, compliance, importance of vitamin D supplementation to the baby and her plan to breastfeed (Appendix 2, not all data processed for this article). Data was entered into a specific study database from the electronic medical record (Cerner, Missouri, USA).