BACKGROUND AND INTRODUCTION The purpose of the Breathe ? Wellbeing, Environment, Lifestyle and Lung Function Study (B-WELL Mom Study) is to examine the role of asthma control in pregnancy outcomes. Asthmasymptoms change during pregnancy, with about 1/3 of women improving and 1/3 of womengetting worse. As such, the study examines poor asthma control in the context of theimmunology of pregnancy and risk factors such as genetics, the environment, and socialdeterminants of health. Women with and without asthma were recruited during the first trimester of pregnancy (< 14weeks gestation) and followed through 4 months post-partum. Assessments occurred duringeach trimester of pregnancy (<14 weeks, 20-22 weeks, 30-32 weeks), at delivery, and 4 monthspost-partum. Maternal asthma status, pre-pregnancy control of asthma, atopy status, lungfunction, inflammatory markers, anthropometrics, behaviors, and demographic informationwere collected and assessed alongside pregnancy outcomes and infant anthropometrics. Primaryexposures of interest included allergies, immune function, and lung inflammation duringpregnancy and postpartum. The primary goals of this project are to explore if atopy status predicts asthma controlvariability; to assess if atopy status is associated with changes in lung function andinflammation; to evaluate the relationship between Treg and Foxp3 on asthma controlvariability; and to evaluate lung function and inflammation in the context of associationsbetween inflammatory markers, air pollutants, and dietary antioxidants. The B-WELL Mom study collected urine, microbiome swabs, and blood samples (PAXGene RNA,serum, plasma, and buffy coat) from approximately 400 subjects at each visit (<14 weeks, 20-22weeks, 30-32 weeks) and 4 months post-partum. Nasal swabs were collected once duringpregnancy while placentas, and cord blood were taken at delivery. Cord blood RNA was collectedat delivery directly into PAXGene. SCOPE The objective of this task order is to explore if atopy status predicts asthma control variability(Aim 1); to assess if atopy status and asthma symptoms dictate patterns of expression ofimmune-related genes (Aim 2); and to determine if asthma status is reflected in the level ofinflammatory markers (Aim 3).