In theory absitinance works; how could it not? But in practice people do not abstain. There's plenty of evidence that abstinence-only education programs are correlated with increased teen pregnancy.
They do in practice. You'll have to explain the lower rates of single family households in the traditionally conservative regions (e.g. Northern Africa and Western Asia). Naturally, because of the strong promotion for a promiscuous and hedonistic lifestyle, and how Christianity has failed in the West, the study you cite does not prove otherwise, as it was only done on a US population.
Edit: a more interesting study would break down the teen pregnancy population in the US by religion or ethnic background to look at the different rates instead of grouping everyone together. The US is not a monoculture.
What you attribute to abstinence, may very well not be abstinence. The traditionally conservative regions you tell me have different values besides abstinence as well.
For example, in Africa and Asia it is much more common that children live with their parents and grandparents for example. This is included in their definition of "single-parent household":
> In this report, single-parent households have a sole adult living with at least one biological, step or foster child under age 18.
Also, it would not explain the difference between Europe and the US. In Europe there are few places where abstinence-only is the norm. While in the US this is much more common. And yet the US has a higher rate of children living in a single-parent household.
> The traditionally conservative regions you tell me have different values besides abstinence as well.
When we look at the dominant religion in those regions I was referring to, we see that Islam places strict guidelines on sexual relationships. So there is a strong causal relationship there. Furthermore, to your point, Islam does promote strong family relationships which can also strongly reduce the problem of single family households. Those two factors are not contradictory.
> Also, it would not explain the difference between Europe and the US
Looking at the map, the vast majority of Europe is still in the orange shade, compared to the heavily blue shade of the countries I'm referring to.
Re-read my post. I said that Islam restricts sexual relationships (abstinence) in addition to promoting family relationships.
Furthermore, there's the fallacy of looking at how Christianity failed in the West, then people generalizing that abstinence doesn't work as I described in my other post.
