If the child is born in Pakistan, s/he would need to be sponsored for PR. I believe Pakistani spousal sponsorship apps are taking at least a year right now in London; a child sponsorship app *may* be a bit faster than that. Additionally, as you are a PR, you would need to be residing in Canada throughout the sponsorship process. You could try for a TRV or TRP for your child but there is a good possibility that s/he would not be able to enter Canada until the sponsorship process is complete, so you would be apart from your child for quite some time.
If it's possible to have the child in Canada, it would be much easier. However, depending on which province you plan to live in, there may be a 2-3 month wait period for healthcare, so you may need to be prepared to pay out-of-pocket for costs until she is covered.
