Sydney woman fighting for life after falling off child's scooter

A woman who fell and hit her head while riding a child's scooter in Sydney's northwest is fighting for life in hospital.

The 68-year-old woman was treated by paramedics at Kellyville about 10pm last night and taken to Westmead Hospital in a serious condition.

Police said she was not wearing a helmet.

A hospital spokeswoman said the woman was in a critical condition today.