During the first trimester, the fertilized embryo's chance of surviving on its own is nil and its rights are tied to the woman's. When the second trimester starts, the fetus is much more viable and has its own rights. Into the third trimester, the fetus is it's own being and the chance of survival with proper medical care is decently likely.
I'm never "for" abortion, but I believe it should be legal during the first trimester. It's sadly become a staple and if made illegal now, would push many women to seek illegal, unsafe procedures. We need to end this problem through proper sex ed, a better economy, and driving home PERSONAL responsibility.
My hope is that by time my sons are old enough to have to worry about this issue, abortion will be a legal medical procedure of extreme last resort. By then there should be better access to birth control for both women AND men. That is what I am working for.