Premature babies born in bigger hospitals are more likely to survive than those born in smaller ones, a new study suggests.
Youngsters born before 33 weeks of pregnancy are 30% less likely to die if they are born in big units treating large numbers of premature babies, researchers said.
And for extremely premature babies born before 27 weeks of pregnancy the figure rises to 50%.
Experts from the University of Warwick, University College London, the University of Westminster and Imperial College London said that health bosses should consider the findings when developing services for neonates in the future.
The study, published in the journal BMJ Open, examined data concerning more than 20,000 premature babies born at 165 NHS neonatal units in England between January 2009 and December 2011.
Of these, almost 18,000 were born when the mother was between 27 and 32 weeks pregnant and the rest were born before 27 weeks.
They found that infants were less likely to die if they were admitted to a high-volume neonatal unit at the hospital where they were born.
Units were classed as "high volume" if their capacity was in the top quartile of the neonatal units assessed.
"High-volume neonatal care provided at the hospital of birth may protect against in-hospital mortality in very pre-term infants," they said.
"Future developments of neonatal services should promote delivery of very pre-term infants at hospitals with high-volume neonatal units."