Objective: Compare neonatal morbidities in women with no prenatal care, and women with inadequate prenatal care, to those with adequate prenatal care. Methods: Retrospective cohort study of neonatal morbidities of 3 exposure groups. Group 1: No prenatal care; Group 2: Inadequate prenatal care; Group 3: Intermediate/adequate prenatal care. Results: 2.5%, 23.3% and 74.1% of subjects (N = 264,138) were in Groups 1, 2 and 3 respectively. Severe neonatal morbidity was more common in Group 1, followed by Group 2, and least common in Group 3. After controlling for gestational age and birth weight, most of these differences were attenuated and not significant except for the following Group 1 vs Group 3 comparisons: meconium aspiration, odds ratio (OR) 2.15 and 95% confidence interval (CI) 1.39 -3.33; suspected sepsis, OR 1.30 and CI 1.13 -1.49; proven viral sepsis, OR 2.23 and CI 1.24 -4.00. Conclusions: Severe neonatal morbidity was most common in those with no prenatal care followed by those with inadequate prenatal care. For most neonatal morbidities, this could largely be explained by gestational age and birth weight differences, but for some neonatal morbidities (meconium aspirations, viral sepsis and dysmorphic features) the impact of no prenatal care persisted after adjustment for these factors.