Vitamin D Levels in Neonatal Umbilical Cord Blood: Factors and Prognostic Analysis

This study is a retrospective-prospective cohort study that investigates the factors influencing neonatal umbilical cord blood 25(OH)D levels, and the impact of exposure to low intrauterine 25(OH)D levels on neonatal prognosis. Newborns born in Sun Yat-sen Memorial Hospital of Sun Yat-sen University from August 2023 to August 2024 were selected. 2ml of umbilical cord blood was collected to test serum 25(OH)D levels. Based on the umbilical cord blood 25(OH)D levels, newborns were divided into three groups: vitamin D deficiency (<30nmol/L), insufficiency (30~50nmol/L), and sufficiency (>50~250nmol/L). Factors influencing neonatal vitamin D levels at birth were investigated by reviewing medical records, questionnaire collection, phone interviews, etc., collecting data on basic neonatal information, maternal information, complications during pregnancy, prenatal biochemical test results, medication history during pregnancy, lifestyle habits during pregnancy, and vitamin D supplementation status. Phone follow-ups on the health of the newborns during their hospital stay and at 1 month and 2 months after discharge were conducted to investigate the impact of exposure to low intrauterine 25(OH)D levels on neonatal prognosis, providing a theoretical basis for early intervention in high-risk pregnant women and early identification of high-risk groups with vitamin D deficiency or insufficiency among newborns.

Miscarriages prevention is a major feature of our hospital's obstetrics department. Many pregnant women who are hospitalized and give birth at our hospital have a history of fetus protection. Choosing pregnant women and newborns from our hospital's obstetrics department as research subjects is conducive to exploring the impact of specific diseases and medication histories on neonatal vitamin D deficiency, which is an innovative aspect of this study.