It wasn't a fender-bender, road debris or broken-down car that clogged Interstate 95 during yesterday morning's rush hour.

Rather, a pregnant woman went into labor and gave birth to a boy on the Aramingo Avenue on-ramp to 95's southbound lanes shortly before 7:30 a.m., an unusual scene that snarled traffic as passing drivers slowed to gawk, said Executive Chief Daniel Williams, a Fire Department spokesman.

When firefighters from Engine 7, which is based at Kensington and Castor, arrived at the scene, the still-damp newborn was curled in his mother's lap, oblivious to his unorthodox entrance into the world. The woman's husband had been driving the car but pulled over to help his wife, Williams said. An emergency medical technician from Engine 7 cut the umbilical cord, he added.

The new mother, recovering yesterday at Temple's Northeastern Hospital, declined to comment. The newborn was her third child, authorities said.

While a roadside birth may be rare, plenty of pregnant women wait until the last minute to head to the maternity ward, city emergency records suggest.

City firefighters and paramedics have gone on 879 "childbirth/labor" runs so far this year and 1,401 last year, Williams said.

"The one thing you can't control is nature, when a baby says: 'Hey, I'm out of here,' " Williams said. *