The woman, said to be in her early twenties, went into labour immediately after getting off a train at Molino Dorino station, La Repubblica reported.
The woman, who had been travelling on the metro with her husband, reportedly had to steady herself as she got off the train, before her waters broke.
Medical staff were quickly on the scene and within ten minute she gave birth to a baby girl.
The mother and baby were taken to Sacco hospital and are reportedly doing fine.
A number of other emergency births have occurred on underground networks around the world, although the event is still rare.
Three have taken place on the London Underground in its 151-year history, the first in 1924 and the latter two within the space of a few months in 2009.
In 2013, a woman gave birth to a baby boy on the platform of L’Enfant (meaning ‘child’ in French) Plaza metro station in Washington D.C.