First: not all pregnant people have consented to sex. They might have been raped.

Second: Some people consent to sex using contraception. So they explicitly have opted out of the pregnant part. If it fails or is sabotaged, they still haven't consented to being pregnant.

Third: Since they can abort, it is very obvious that they can decide if they want to continue or not. So only explicit consent to carry the pregnancy to term means consent. Not just that, if the pregnancy goes wrong, they can decide to stop it even if they initially consented. Imagine for example that pregnancy provoques diabetes in a woman. So giving birth would rend her blind. Well, maybe that woman deserves to change her mind. Or that the pregnancy would kill her. Or she finds out that she has cancer and need chemotherapy and for that she needs to abort.

Each person has their reasons. You want to decide for them and that they endure the consequences of your choice. Not you, them. How is that moral?