ObjectiveThe early recognition of possible labour onset symptoms may be pivotal to identifying the beginning of early labour and are usually recognised by the birthing women themselves. The present study illustrates the interrelationship among five labour-onset symptoms and explores the association of these labour-onset symptoms with the self-diagnosed labour onset of primiparas. MethodsA prospective cohort study on a sample of 69 primigravida in Giessen, Germany, expecting spontaneous onset of labour at term. The participants filled in a diary from ≥37 + 0 weeks gestation until self-diagnosed labour onset. Descriptive, bivariate and inferential analysis explored association of labour onset symptoms with self-diagnosed labour onset while accounting for maternal and newborn characteristics. ResultsSelf-diagnosed labour onset was positively associated with all symptoms and clinical characteristics, apart from irregular pain and maternal weight and age. Moreover, regular pain was negatively correlated with irregular pain; having regular pain increased the odds of self-diagnosed labour onset substantially (OR: 10.18, 95 % CI: 2.39–66.27), followed by gastrointestinal symptoms (OR: 2.07, 95 % CI: 0.40–13.10) and emotional symptoms (OR: 2.05, 95% CI: 0.30–13.98). ConclusionBeing the initiator of intrapartum care without any birth experience, primiparas are prone to experiencing dissatisfaction in care and may enter professional care too late or too early. The present study showed that regular pain may signify primiparas to self-diagnose labour onset within 24 h and indicate early labour symptoms that may be relevant for a self-diagnosed labour onset.