Some general observations:

Typically, those who oppose most or all abortions see it as murder, not different from infanticide. Talk of choice or rights for the pregnant woman is nonsensical in this context. Most of the arguments espousing this point of view focus on getting others to accept what seems to be the glaringly obvious fact that it is indeed murder. These arguments largely fall on deaf ears.

Typically, those who oppose most legal restrictions on abortion see it as a medical procedure, similar perhaps to having surgery. Talk of murder is irrelevant (the embryo/fetus/child is not legally a human being). Most of the arguments espousing this point of view focus on getting others to refrain from interfering in what seems clearly to be personal medical decisions, said arguments likewise largely falling on deaf ears.

To a large degree it hinges on one's personal perception of what constitutes a human being. For most purposes, one is legally a human being starting at birth, though the law muddies this somewhat with consideration for loss of an unborn child in some circumstances. Many essentially accept this view. Conversely, many others (including the Roman Catholic church, I believe) consider that a human being exists from the moment of conception. This is not very workable, however, as a legal concept, in that we don't have a feasible method for determining when/if conception occurred. If I kill your wife two days after you've had intercourse, have I killed one person or two? What about insurance for the loss of the child?

Many people would say that the critical point comes somewhere between conception and birth. Just when this line is crossed will vary from one person's perception to another, and sometimes will vary within one individual's thinking. The "partial birth abortion", coming rather close to the time of normal birth, and somewhat resembling birth, is naturally going to push a lot more buttons than a first trimester evacuation of tissue that does not much (or at all) look like a baby.

If you kill a person walking down the street for no reason other than you just feel like doing it, 99.9% of the people in this country (U.S.) will agree that it is murder, as does the law. No real debate or argument here. Perform an abortion, and it's not nearly so clear cut--roughly half will call it murder, roughly half will not, many are of (at least partially) mixed feelings. The laws tend to reflect this lack of national certaintly, varying from state to state and time to time.

Given the lack of a strong national consensus that abortion is always/usually murder, and the difficulties in establishing that a legal human being exists before birth, I would rather there be mimimal legal restrictions on abortion. I'm not even sure where I would personally draw the line if my wife were pregnant (it seems like an academic exercise to ponder that), and I wouldn't feel comfortable telling anyone else where they should draw the line.