Vitamin D gets a lot of attention, and it should, mainly for its known role in bone stability. However, vitamin D has significant additional roles in physiology. Vit D, and its metabolites, also functions as modulator of inflammatory and immune responses. According to a number of recent studies, this important micronutrient plays a complex role in numerous biochemical pathways in the immune system and disorders that are associated with them. In pregnancy, the association of Vit D deficiency and adverse perinatal outcomes has been controversial with conflicting data. Nonetheless, in August 2024, the Endocrine Society published its recommendation (J Clin Endocrin Metabol) for routine supplementation for children, adults older than 75 years, pregnant women, and adults with prediabetes. In this episode, we will review a new publication (Feb 2025) from the Am J Clinical Nutrition regarding low vit D levels in the first trimester and PTB. Could vit D supplementation be the answer for preterm birth prevention? The answer may surprise you! Listen in for details.