A woman would not get pregnant from performing or receiving oral sex.
If someone believes they are the father of a child they do have certain rights under Canadian Law. As we are a sexual health information page we do not have any experience with providing any legal advice.
I would suggest contacting a lawyer in regard to your legal options. With a Google search I did find a family lawyer’s office in BC that specialise in these particular cases, they have a phone number you can call to discuss your personal situation with them. Just click on the link.
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