Background <p>While maternal psychological stress during mid-to-late pregnancy has been linked to offspring allergies, the impact of early pregnancy distress remains unclear. This study investigates the association between maternal depressive and anxiety symptoms in early pregnancy and allergic diseases in offspring.</p> Methods <p>Based on a birth cohort of 5263 children, antenatal depressive and anxiety symptoms in early pregnancy were assessed via the Patient Health Questionnaire and Generalized Anxiety Disorder Questionnaire, respectively. Allergic outcomes, including asthma, atopic dermatitis (AD), and allergic rhinitis (AR), were evaluated via structured questionnaires. Relative risks (RRs) with 95% confidence intervals (CIs) were estimated via generalized linear models, whereas restricted cubic splines were used to explore linear and non-linear associations between maternal distress and allergic outcomes.</p> Results <p>Maternal depressive symptoms in early pregnancy were associated with an increased risk of AD [adjusted RR (95% CI) = 1.15 (1.03–1.29)] and AR [1.52 (1.29–1.79)]. Maternal anxiety symptoms in early pregnancy were associated with increased risks of AD [1.11 (1.02–1.21), mild anxiety] and AR [1.33 (1.04–1.68), moderate to severe anxiety]. Dose‒response analyses revealed graded relationships between distress severity and allergic outcomes. In the joint analysis, comorbid depression and anxiety in early pregnancy were associated with an increased risk of AD [1.15 (1.05–1.26)] and AR [1.42 (1.23–1.63)]. Subgroup analysis revealed a greater risk of asthma for boys born to mothers with mild anxiety [1.95 (1.20–3.15)] but not for girls.</p> Conclusion <p>Maternal distress in early pregnancy is associated with an increased risk of allergic diseases in offspring during toddlerhood.</p> Graphical Abstract <p></p>