Maternal Vitamin D Concentration in Mid-pregnancy and Its Effect on Fetal Thymus Size: A Report from a Tertiary Center in Iran

Background & Objective: The thymus gland significantly affects fetal immune system maturation. Additionally, there is a linear association between size and its performance. Given the high prevalence of vitamin D deficiency in Iran scarce studies with conflicting results, subjecting maternal concentration effect on thymus, we decided to investigate relation mid-gestation. This study also aimed generate race-specific reference range.Materials Methods: We performed cross-sectional ultrasound measurements at 18-22 weeks gestational age 94 pregnant women correlation serum levels from May July 2021 tertiary center Imam Khomeini Hospital Tehran, Iran.Results: mean values perimeter, thymus-thoracic ratio, transverse diameter, area all participants were 4.18±0.56 cm, 0.37±0.04, 1.56±0.21 1.11±0.76 cm2, respectively. There was trend toward decreased perimeter diameter decreasing level D. significant biometric indices age. Furthermore, observed diameter. Conclusion: generated nomogram for Iranian women. Moreover, requires further prospective investigations. A low compliance daily intake during pregnancy shown, which solution.