Vitamin D Levels in Umbilical Cord and It's Impact on Infant and Children's Health (VITADi Study)

Participants of this study are women in the third semester of pregnancy, who consented to be included with their babies in this study. Firstly, the parents will be given explanation regarding the study, and informed consent will be signed if they agree to participate. All the pregnant women who met the criteria will be recorded for their name, age, parity, birth and medical history. Anthropometric examination will be done on the pregnant women, to measure weight using standardized CEBA digital scale, height and upper arm circumference. Blood sampling will also be done to measure complete blood count, ferritin, Fe serum, vitamin D levels, calcium, parathyroid hormone, IL-6 and IL-10.

After the subjects give birth, the babies who met the criteria (aterm, birth weight > 2500 grams, with no congenital abnormalities and acute infection at birth) will also be included in this study. Measurement of birth weight, birth length, and head circumference will be carried out along with blood sampling by taking 3 ml of blood from umbilical cord, 1,5 ml each to measure the complete blood count, and other 1,5 ml to measure ferritin, Fe serum, vitamin D levels, vitamin D receptors, IL-6 and IL-10. Subjects will be monitored for 6 months, and two home visits will be done throughout the study at the age of 3 months and 6 months. During the visits, subjects will be measured for their weight, length, head circumference, as well as their nutritional status. Parents and guardians will also be asked questions regarding the incidence of diarrhea, allergic manifestations such as rash, and assessment will be made based on Hanifin Rajka criteria. At the age of 6 months old, blood sampling will be done again by taking 3 ml of the blood, 1,5 ml each to measure the complete blood count, and other 1,5 ml to measure ferritin, Fe serum, vitamin D levels, vitamin D receptors, IL-6 and IL-10.

The collected data then will be grouped based on the purpose and type of data, then univariate analysis and bivariate analysis will be performed. Univariate analysis will describe the characteristics of the basic data, in the form of frequency, mean value, standard deviation, and range. Meanwhile bivariate analysis such as Wilcoxon test will be performed to to analyse data with independent variables with an ordinal/numeric scale, the data are not normally distributed and have different variances. Mann-Whitney test will also be performed test to compare ordinal or numeric scale variables whose data are not normally distributed and have different variances between two unpaired groups.