The decision to terminate a pregnancy should always be left to the woman who is pregnant. No one, not government, church, or the man who impregnates her should have any part in the decision making process. The cause of the pregnancy should not have to meet any arbitrary criterion such as rape, incest, failed contraception, etc. Simply stated, women should be entitled to full control over their own bodies just as men are.
There are many situations that may come up that can result in an unwanted pregnancy, including (but not limited to) cases of rape, incest, or failed contraceptive use. To say that a woman would have to go through a pregnancy that they are unwilling or unable to complete is a slap in the face to their rights as a person. Why force a woman to give birth to a baby that she does not have the means or desire to take care of? So there would be more people on the street?
In the USA, anyway, it is absolutely up to the mother what she wants. Otherwise? The father should have some input into the matter, but circumstances often prevent that. Look, what one must consider is if it is a life we are destroying, and if that is proper. Any "choosing" mother should at least consider that.
A woman should be able to determine whether she wants to terminate a pregnancy. There should be some basic safeguards in place, however, to protect the interests of fathers in cases other than rape or incest. If a baby is growing inside of a woman, the man should at least be notified if an otherwise viable pregnancy is terminated.
One person's rights end where another's rights begin. So, unless the woman was raped she compromised her right to her autonomy herself. She can't claim that the child is somehow violating her rights, her body, etc. When the choices she made (along with her) are the only reasons the child is there in the first place.