Objective To investigate urinary/faecal incontinence (UI/FI) prevalence during pregnancy and postpartum, and the main risk and protective factors, in a large Italian population. Design Prospective observational analysis of patient-reported outcome (PRO) measures. Population and setting All pregnant women agreed to participate to the systematic and longitudinal survey on the maternity pathway in Tuscany, Italy. Methods We employed data from four questionnaires completed by women from the beginning of pregnancy until six-months postpartum. Each questionnaire included two PRO measures – the Wexner scale for FI and the International Consultation on Incontinence Questionnaire for UI –, and several questions investigating the socio-demographic and clinical features of respondents. Main outcomes The UI/FI prevalence at each time-point and the related risk and protective factors. Results Among our 6,023 respondents, UI prevalence in the third trimester was 24.3% and almost halved six-months postpartum. Women reporting FI were 6.2% in the third trimester and 4.2% six-months postpartum. Higher UI occurrence and severity were found in highly-educated, aged > 30, and overweight/obese women. Caesarean-section was protective against postpartum UI, while spontaneous tear or episiotomy were risk factors. Protective effects were provided by performing pelvic-floor-muscle-training during pregnancy, mainly for specific risk groups. Furthermore, higher FI prevalence and severity emerged in overweight, aged > 40, highly-educated, non-Italian women and in those undergoing tear. Conclusion PRO measures systematically and longitudinally collected in a large Italian population highlighted the prevalence of pregnancy-related UI/FI and the risk and protective factors. Pelvic-floor-muscle-training may be recommended in women with peculiar socio-demographic and clinical features.