Hector Morales and his wife Kathryn Engle were heading to the hospital in suburban Cicero, Ill., early Wednesday when they became stuck in a traffic jam, Cicero town spokesman Ray Hanania said.
The stand-still was caused by an earlier accident in which one woman was killed, ABC News reported. Two other people in the crash -- the driver and another passenger -- are in serious condition at a hospital.
When he realized traffic wasn't moving fast enough to get his wife to the hospital in time for the birth, Morales got out of the car and waved down police and firefighters who had been directing traffic, ABC News reported.
The officers helped Engle deliver her baby -- a boy named Aidan -- from the couple's car. The family was then rushed to the hospital in Cicero.
"It saddened us to just find out of the terrible accident that took place hours before. Our condolences to the families," Morales said in a statement. "I do want to thank the Cicero police and fire department[s]. The 911 dispatch center guided us quickly and calmly. At this time, mom and baby are resting and bonding, our family members are visiting and our thanks go out to everyone."