Some pro-lifers point out that many women seeking abortion were using (or misusing) some type of contraception when they conceived. Sometimes pro-lifers cite this fact as evidence that contraception does not decrease, and may even increase, abortion.
But this conclusion is misguided. It seems likely that women who don’t want to be pregnant are more likely both to use contraception and to seek abortion than women who actively want to be pregnant or women who are ambivalent about pregnancy. If that’s the case, we have a correlation/causation problem.
|Which means I get to use an XKCD comic in my blog post!|
In order to talk about whether contraception increases, decreases, or has no effect on abortion, we need to look at studies that have control groups. Ideally, a control group is identical to the experimental group in every way except for the one factor you want to analyze. As my beloved Wiki explains:
Scientific controls allow an investigator to make a claim like “Two situations were identical until factor X occurred. Since factor X is the only difference between the two situations, the new outcome was caused by factor X.”
In the case of contraception and abortion, ideally we would have research that compares a control group of women to an experimental group of women. The two groups would be identical in terms of relationship stability, financial status, beliefs about abortion, feelings about pregnancy, and any other relevant factors. The control group of women would use no contraception, and the experimental group of women would use contraception. Then we could compare the rates of unplanned pregnancy and abortion for each group, and we could more reasonably talk about how contraception affects abortion rates.
A big part of the contraception debate is whether contraception actually decreases unplanned pregnancies. One side cites research showing the rate of unintended pregnancies is much lower for sexually active people who use contraception than for those who don’t.
The other side counters that not everyone would necessarily be as sexually active if contraception wasn’t so widely available. This side talks about risk compensation – the idea that if people believe contraception makes sex less risky, those people will make riskier sexual decisions. For example, they may choose to have sex more frequently, in less committed relationships, or with less careful attention to the woman’s cycle.
The fact that many women who have abortions were using contraception when they got pregnant doesn’t tell us anything about how contraception affects pregnancy rates. To illustrate the problem, here is a hypothetical situation using entirely made up numbers:
Suppose we have two groups of 100 women each. The first 100 women, called the Nope group, really don’t want to be pregnant. 90% of them use contraception, and 100% of them will choose abortion if pregnant. The second 100 women, called the Meh group, are either open to or ambivalent about pregnancy. 10% of them use contraception, and 17% of them will choose abortion if pregnant.
|Each symbol represents 10 women.|
Now let’s say 20 of the Nope women and 60 of the Meh women get pregnant, so 20 of the Nope women and 10 of the Meh women choose abortion. So 30 women are abortive.
|If 90% of Nope and 10% of Meh used contraception.|
For simplicity, let’s assume their abortion decisions aren’t related to whether they used contraception, so 90% of abortive Nope women (18 women) and 10% of abortive Meh women (1 woman) were using contraception. That means 19 out of the 30 abortive women were using contraception when they got pregnant, or 63% of abortive women were using contraception when they got pregnant!
Yet, in this scenario, contraception did greatly decrease pregnancy rates. The Meh women were three times as likely to get pregnant as the Nope women. If, like the Meh women, only 10% of the Nope women used contraception and 60 of the Nope women got pregnant, all 60 of those Nope women would have chosen abortion. Then there’d be 70 abortions instead of 30.
|If 10% of Nope and 10% of Meh used contraception (scenario 1).|
From this perspective, using contraception decreased abortions by 57%!
Alternatively, what if less contraception meant less risky sexual choices? Suppose again only 10% of Nope women use contraception, but this time suppose they’re so careful about sex that only 10 of them get pregnant. Then there’d be only 20 abortions instead of 30.
|If 10% of Nope and 10% of Meh used contraception (scenario 2).|
In this scenario, not using contraception decreased abortions by 33%!
The point is, without control groups, we don’t know which way it would go. We can (and do) have strong opinions about how we think it would play out, but until we cite research with control groups, we’re really just guessing. Simply saying “most of the women who got abortions had been on birth control” doesn’t tell us one way or another how the abortion rates would be if less women used birth control.
|404 Error: Insufficient Data|
That doesn’t mean the fact is irrelevant. If nothing else, we know contraception alone will not eliminate abortion. And I think it’s true that there are plenty of pro-choice people who implicitly understand this idea, and see abortion as the “safety net,” a back up form of birth control.
But there’s a big difference between saying “contraception won’t fully eliminate abortion” and “contraception makes no difference in abortion rates” or even “contraception increases abortion rates.” The point about abortive women using contraception only speaks to the first statement, not the second two statements. For those statements, you need more information.