An 18-year-old woman was in serious but stable condition in hospital after she was hit by a taxi while cycling in Ottawa's west end Wednesday morning.

The cyclist's head hit the windshield of the taxi and she was thrown about the length of a parking space before landing on the road near Robertson Road and Vanier Street in the Bells Corners neighbourhood at about 9:30 a.m. ET, said an Ottawa paramedic service news release.

The woman, who was not wearing a helmet, received serious head injuries, as well as a leg fracture and an injury to her hip, said J.P. Trottier, a spokesman for the paramedic service.

Trottier said most calls to the paramedic service about cyclists involve head injuries.

"There are not a lot of circumstances where [a] helmet would not have made a big difference," he added.

Ottawa police closed Robertson Road between Moodie Drive and Richmond Road for an investigation.