What kind of relationship do you want with your child?
In the United States the laws regarding child custody are horribly slanted against fathers, and I would imagine that Canada would be little different.
An unmarried father has literally NO rights regarding his child. The mother has full and sole custody, and can withhold contact from him, force him to go through prohibitively expensive legal procedures in order to get even minimum visitation, and can even put the child up for adoption against his knowledge or against his will.
For these reasons, you might consider marrying her to establish your paternity rights, just in case the relationship goes south.