Abortion is pretty much a necessity for modern life, for several reasons.

1) Without abortion, women's liberation is impossible. These days women must delay marriage and childbearing to focus on their careers. However, it would be unreasonable to expect them (or men, for that matter) to abstain from sex entirely through their mid to late twenties. True, we have contraceptives, but they aren't fool-proof; abortion is the "safety net." So either you give women the right to abortions, or you counsel them to return to their traditional role as mothers and wives. But for a number of obvious reasons, the latter option has been ruled out entirely. So you're left with abortion.

2) Similar to the first reason, abortion is necessary in a modern society because traditional patterns of courtship and mating have been disrupted by things like industrialization and social modernization. In the past, (ideally) both partners would be virgins at marriage, and they would engage in sexual intercourse only within the bounds of marriage. Whether or not this was always the case is something else entirely, but that, at least, was the ideal held up by society. But now this sort of thing is no longer viable for a large number of people. Both men and women have to delay marriage and childbearing, but they can't realistically be expected to abstain from sex for 25+ years. Even if they wanted to get married young, it wouldn't matter, because things like school, work, etc. force them to relocate constantly, typically breaking them up. So, again, abortion is needed because people are forced to engage in "risky" sex, i.e., sex outside of wedlock.

3) People just want to have free sex. They want that more than almost anything else. But, again, contraceptives aren't fool-proof. So, if they want to have sex for pleasure, abortions are needed.

Basically, what I'm getting at here is that unless you can think of a way to turn back the historical processes of the last, say, 200 years or so, you are kinda forced to accept abortion, regardless of what your moral sentiments happen to be.