Both terms, "pro-life" and "pro-choice", are heavily loaded. Pro-life far more so than pro-choice, but still.
What is actually meant by "pro-life" is "opposed to legalization of abortion".
What is actually meant by "pro-choice" is "for the legalization of abortion".
It should however be noted that even extreme pro-choicers are not nearly so much for abortion as they are for having legal protection for abortion. There is a very significant difference there, one that may easily translate into perhaps surprising consequences.
Pro-choicers do not like abortions. Even under ideal circunstances, abortions are very traumatic experiences that no one actively pursues or enjoys. But realistically, people have to make choices in their lives, and the blunt fact is that quite often people don't see how they could possibly be good parents at the time of pregnancy.
The perception, unfortunately all too often an accurate one, is that it is more healthy and considerate to abort an embryo early and legally than to deal with an unwanted pregnancy in ways that would penalize all people involved, including the infant. One part of it is the very realistic observation that forbidding abortion does not make it much less likely to occur. It just makes abortions clandestine and riskier. A person who does not feel ready to engage at parenting will not feel better prepared or more able simply because the law says that he or she has no choice.
Nor is the "pro-life" stance necessarily more considerate than its opponent, either. A considerable part of that movement is not even very sincere or coherent, quickly pursuing clandestine abortions when the convenience presents itself, even while their public face insists on the wrongness of it all.
Quite simply, pro-life families are not always significantly less scared of unwanted pregnancies than anyone else, nor do they have a lot more in the way of constructive options.
Lessening the frequency of abortions is (or should be) pretty much an universal goal, even for pro-choicers. But the ways of attaining such a worthy goal probably do not even include forbidding abortions. Instead, effective, realistic sex education is a much more effective measure. So is honest, loving dialog among adults and teenagers. So is pursuing better structure for the adoption of unplanned children.
The main reasons why abortions happen so often are poor sexual education (often naively insistent on "abstinence only"); social stigmas both on abortion itself and on unplanned, out-of-wedlock pregnancy; faiiure of the parents on duly teaching their children about prevention of pregnancy; and this odd cultural expectation that people should hide their mistakes instead of handling them at the light of the day.
Were people able to freely speak that they did not mean to have children and would welcome some support in preventing pregnancy or, failing that, finding willing and loving adoptive parents, abortion would be far less of a problem.
Law is not really helpful in avoiding abortions. It may easily be an aggravator instead.