She crouched on the floor in front of the passenger seat and Mr Keating prepared to rush his pregnant wife to hospital, which in normal traffic would have been 20 minutes away.

But in the rush hour the journey was likely to take far longer.

With traffic not moving Mr Sherry set the car’s navigation system to take them to the hospital in the suburb of Paoli and trusted the Tesla’s advanced driving features- relying on sensors and radar to avoid collisions – to do the rest

Keeping one hand on the wheel, Mr Sherry tended to his wife, squeezing her hand as the car inched its way to its destination.

Then as they arrived Mrs Sherry whispered: “Oh, my God, Keating. She’s out.”

Fortunately, a paediatrician happened to be passing by, who summoned nurses who cut the umbilical chord on the car’s front seat.

“Once the paediatrician said, ‘She’s healthy. Congratulations,’ that was quite the sigh of relief,” Mr Sherry added.

The birth was regarded as something of a novelty by nurses who flocked to see the “Tesla baby”, who was named Maeve Lily.

Her safe arrival was testimony to Tesla’s autopilot mode, which has generated controversy after a series of accidents in which drivers have left the car to drive itself.

The company insists the autopilot technology is intended to help the driver who should always remain in control of the car.