Outcomes
Adverse neonatal outcomes were stratified into neonatal infection and asphyxia-related conditions, defined by registered ICD-10 diagnoses in the Swedish Pregnancy Register. Neonatal infection included necrotizing enterocolitis, congenital pneumonia, sepsis, urinary tract infection, skin infection, umbilical infection and unspecified infections during the neonatal period. Asphyxia-related conditions included meconium aspiration, hypoxic ischemic encephalopathy, convulsions/seizures, hypoglycemia, jaundice and respiratory distress syndrome (RDS). (ICD-codes are available in Supportive information eTable 4).