I’m a Philly neonatologist, and every time I discharge a baby from the NICU, I worry about the air they’ll breathe at home

The same polluted air that may have contributed to a baby's preterm birth is also a risk when the vulnerable baby goes home. Nenov/Moment Collection via Getty Images

Discharge day in the neonatal intensive care unit, or NICU, should feel like a finish line. After weeks or months of monitors, alarms, oxygen, feeding tubes, blood tests and waiting, a family can finally take their baby home.

As a neonatologist, I know how much work it takes to get that baby there. Their lungs have grown stronger. Their feeding has improved. Their medications have been adjusted and readjusted. The car seat test has been passed.