Vitamin D Status of Mothers and their Neonates in North Texas
This is an observational prospective study of the vitamin D status of mothers at delivery. Screening for eligible patients entails generating a list of mothers who delivered the day prior from the electronic medical records. Patients will be subsequently recruited from the postpartum wards of PMH. The immunology lab and blood bank at PMH will be initially contacted to determine whether sufficient quantities of maternal waste and cord blood exist for these potential subjects to determine 25-OHD levels. If qualified, subjects will be invited to participate in the study, and written consent will be obtained from them prior to participation.
Consented post-partum women will be asked in an in-person or telephone interview questions pertaining to their medical history and lifestyle during their pregnancy. Additional information regarding maternal medical history, delivery events and infant history will be extracted from the maternal and infant medical record. The maternal daily calcium intake during pregnancy will be assessed by a Rapid Assessment of Calcium Method questionnaire, which has been validated in adults .
After completing the questionnaire, 1 mL of maternal waste serum from blood drawn at delivery per standard of care will be collected from the PMH Immunology lab and 1 mL of serum from cord blood will also be collected from the PMH blood bank to obtain a 25-OHD level. It is standard of care for cord blood from every delivery to be stored in the blood bank at PMH for up to 7 days. The amount of blood that is collected at delivery varies from 1-10 mL. Due to financial or logistical reasons, samples may be kept frozen in a co-investigator[Right Quote]s lab for batch analysis. Approximately 0.3 mL of serum from both maternal blood and cord blood will be sent separately to Children and amp;apos;s Medical Center to obtain a 25-OHD level. The remainder of each blood sample will be frozen and stored at -80 degress Celsius in a co-investigator[Right Quote]s lab in case a 25-OHD level needs to be repeated secondary to lab handling error. Any stored blood specimens will be discarded at the completion of the study.
The prevalence of vitamin D deficiency and insufficiency will be determined for the population as a whole and stratified by season and ethnicity. We will also determine correlations between maternal and cord blood 25-OHD levels and between these levels and the maternal, neonatal and delivery characteristics collected from the medical chart or via interview/questionnaire.
1) All pregnant women 16 years of age or older who deliver a viable neonate at PMH
2) Subjects able to provide written informed consent in the 24-48 hours following delivery
3) All ethnicities and both English and Spanish speaking subjects
4) Subjects who have sufficient waste blood and umbilical cord blood for sending a 25-OHD level