The accident happened around 7 a.m. Saturday near the intersection of Herndon and Millburn.
Officers say the mom was pushing her baby in a stroller down a narrow frontage road with a group of friends when a white Ford sedan hit her.
The force of the collision broke the mother's leg. The stroller was thrown down the street but the child was not injured.
Investigators say the fact that the baby was buckled in, probably saved its life.