That is patently absurd. Consent to sexual intercourse is not consent to pregnancy, especially if contraceptives were used and failed.
At the risk of stretching the metaphor to its breaking point, this is you choosing to go out and get drunk while aware that members of an unethical music lovers' organization are skulking about looking for victims to graft sick violinists onto. Sure, they no longer need to actively drug you because you willingly did that yourself, but that doesn't imply your consent to what happens next.
At the risk of stretching the metaphor to its breaking point, this is you choosing to go out and get drunk while aware that members of an unethical music lovers' organization are skulking about looking for victims to graft sick violinists onto. Sure, they no longer need to actively drug you because you willingly did that yourself, but that doesn't imply your consent to what happens next.