Most of the discussions on this forum focus on abortion and the poor, and not so poor, single women. However, there are many, many women who are married and have (with their husbands) made the decision to terminate a pregnancy. Their reasons start at the money issue (it's extremely expensive to raise - feed clothe and educate- a child) to emotional issues (not enough time to spend with with a baby) to physical issues (one or both of the parents are unable to physically deal with a baby) or the baby is horribly deformed/disabled (and it's hard to watch you child die slowly and painfully).
So abortion is legal in the US and many other countries, because we understand that a woman's body is her own and that she should be the only one to control it. But, many times, abortion is the best way for all concerned - including the unborn.