Background/objectives: Functional gastrointestinal disorders (FGIDs) are a heterogeneous group of conditions of unclear etiology. The biopsychosocial model approach to FGIDs posits that early-life stressors may trigger a cascade of complex interactions between genetic predisposition and risk factors eventually leading to the occurrence of FGIDs. The relationship between the psychological disposition of the mother and FGIDs occurrence is poorly understood. We conducted a study to investigate if parental psychological factors may contribute to the onset of FGIDs in offspring., Methods: We performed a prospective cohort study of parent-infant pairs who completed a battery of self-reported psychological questionnaires and a validated Rome III questionnaire for the diagnosis of infant and toddler FGIDs. The Edinburgh Postpartum Depression Scale (EPDS) was used to examine postpartum depression (PPD) symptoms; the Maternity Blues Questionnaire (MBQ) was applied to measure maternity blues severity; the Symptoms Checklist-Revised (SCL90-R) was used to assess the presence of relevant psychiatric symptoms; adult attachment style in mothers was assessed in a continuous way through the five dimensions of the Attachment Style Questionnaire (ASQ)., Results: Out of the 360 eligible mothers, 200 were enrolled, 113 completed the 3-month follow-up and were included in the final analysis. PPD symptoms prevalence was 20.4%, 20%, 13.2%, and 13.1% respectively at 3 days, 1 week, 1 month, and 3 months after delivery. 40.4% of mothers suffered from severe blues according to the MBQ. Relevant psychiatric symptoms (SCL90-R) were present in 7.8% and 10.9% of mothers, respectively at 1 week and 3 months after delivery. 48.7% of mothers showed a secure attachment pattern measured through the RQ. At 1-month follow-up, infant regurgitation was diagnosed in 26 (23%) of infants, infantile colic in 31 (27.4%), dyschezia in 17 (15%), and functional constipation in 9 (8%). At 3-month follow-up, FGIDs prevalence was respectively 16 (19.3%), 11 (13.3%), 4 (4.8%), and 11 (13.3%). A significant positive association between PPD symptoms starting 3 days after delivery and the presence of infantile colic on setting 1 month after birth was found (P = 0.028), as well as between PPD symptoms occurrence 7 days after delivery and infantile regurgitation beginning 1 month after birth (P = 0.042). A higher prevalence of infantile colic was found in the offspring of mothers suffering from PPD symptoms from 3 days after delivery (54.5 vs 19.8; P = 0.001). No significant association was found between FGIDs and psychiatric symptoms and maternity blues at any timepoint. On the other hand, mothers of infants with regurgitation with an onset 1 month after birth have higher insecurity score in avoidant and fearful ASQ-related attachment dimensions (respectively, P = 0.03, P = 0.042, P = 0.03)., Conclusions: Maternal psychological factors might contribute to the onset of infant FGIDs in offspring. Early screening of postpartum depression symptoms and early implementation of psychological interventions within the postpartum period might promote the health of the mother-infant dyad., Competing Interests: Conflicts of Interest and Source of Funding: The authors certify that they have no affiliations with or involvement in any organization or entity with any financial interest, or non-financial interest in the subject matter or materials discussed in this manuscript., (Copyright © 2021 by European Society for Pediatric Gastroenterology, Hepatology, and Nutrition and North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition.)