But the study did find that women who went to private religious schools were more likely to have had an abortion.
The effect of schools was really dramatic. A woman who had gone to a religious school was 5 times more likely to have had an extra-marital abortion than a woman who went to a state school.
On the face of it this is a pretty strange result. The researcher, sociologist Amy Adamczyk at City University of New York, thinks it may be down to social pressures against extramarital births:
"Religious school attendance is not necessarily indicative of conservative religious beliefs because students attend these schools for a variety of reasons," Adamczyk said. "These schools tend to generate high levels of commitment and strong social ties among their students and families, so abortion rates could be higher due to the potential for increased feelings of shame related to an extramarital birth." (Press release)
There's another possibility, of course. It might be that students who go to religious schools have restricted access to contraception. This would fit with an earlier study which found that teenagers who make virginity pledges are no more likely to abstain from sex, but are less likely to use contraceptives. It also fits with evidence that more religious countries have higher abortion rates.
So what else lowered the abortion rate? Well, the press release and a lot of the media reports picked up on the fact that Protestants were less likely than Catholics and women of other faiths to have an abortion.
But what they don't mention is the fact that having no religion was just as effective at reducing abortions!
Here are the data: Conservative Protestants were 48% less likely to have their first pregnancy end in abortion. The reduction in women with no religion was 43%. Those two numbers are statistically indistinguishable.
Now, this is not because women with 'no religion' were better educated, or from wealthier homes, or had higher college aspirations, or any of the extenuating circumstances that might otherwise account for the effect. All these were taken into account in the analysis.
Nope, it's freedom from religion, pure and simple, that led to fewer abortions."