The unpredictable nature of childbirth infrequently results in unplanned out-of-hospital birth, in a pre-hospital setting. We evaluated the perinatal and long-term outcome of children accidentally born out-of-hospital. This was a population-based analysis of singleton deliveries occurring at a single tertiary hospital. The maternal characteristics and pregnancy outcome of unplanned out-of-hospital births were compared with in-hospital attended deliveries. Long-term cumulative incidence of hospitalizations (up to 18 years) involving respiratory, neurological, endocrine or infectious morbidity were evaluated using Kaplan–Meier survival curves and Cox regression models were used to control for confounders. In total, 243,682 deliveries were included, and 1.5% (n = 3580) were unplanned out-of-hospital births. Most occurred in multiparous women, and about a quarter of these women had inadequate prenatal care. Perinatal mortality rate was significantly higher for out-of-hospital births as compared with in-hospital births (OR = 2.9; 95% CI 2.2–3.8, p < 0.001). Kaplan–Meier survival curves demonstrated a significantly lower cumulative incidence of hospitalizations of children born out-of-hospital and the Cox models showed that hospitalization rates involving any of the above morbidities were significantly lower in children born out-of-hospital. While perinatal mortality was higher in unplanned out-of-hospital births, offspring born out-of-hospital showed a lower incidence of hospitalizations involving a variety of morbidities, possibly owing to under-utilization of healthcare services in this population.