Playing devil's advocate... what if I (as a man) consent to sex because she says she's on the pill? And then she's not? In Canada, having sex without a condom

Playing devil's advocate... what if I (as a man) consent to sex because she says she's on the pill? And then she's not? In Canada, having sex without a condom is "sexual assault", and is criminal. Lying about birth control isn't a crime because (paraphrasing the judgement) "No physical or economic harm has been done". 18 years of paying child support apparently isn't "economic harm".