The objective of this study was to identify factors that predict ambulation in spastic quadriplegic cerebral palsy. A 4-year registry-based birth cohort was searched for patients with a diagnosis of spastic quadriplegic cerebral palsy. All patients were then divided in 2 groups: (a) Gross Motor Function Classification System level < or = III (ambulant group) and (b) Gross Motor Function Classification System level > or = IV (nonambulant group). Clinical features were then compared between the 2 groups. A total of 85 children with a diagnosis of spastic quadriplegic cerebral palsy were identified. Of these, 65 and 20 were classified in the ''nonambulant'' and ''ambulant'' groups, respectively. The presence of seizures in the first 24 or 72 hours of life and the administration of antibiotics during pregnancy/delivery were all associated with an eventual inability to achieve ambulation. A gestational age < or = 27 weeks, birth weight <1000 g, Caucasian mother, and the presence of hyperbilirubinemia were significantly linked with independent ambulation.