The woman always has the choice to abort. No one can force a woman to become a mother. Other than the rare case of rape the basis for requiring abortion be legal is that it isn't seen as reasonable to require a woman to give up sex unless she wants to accept the risk of having a child. It is unreasonable to expect that men give up sex. 
There is a huge difference between the odds he thought he was accepting and the odds he actually got because of her misrepresentation. 
If a doctor lied to a patient about the chances of serious adverse effects of a medication and those effects then occurred I bet you wouldn't be arguing in favour of the doctor.