When I was a teenager and saw other pregnant teenagers at my Arkansas high school, but none at my California high school, I assumed that the Arkansas kids were fooling around more.
I realize now that probably wasn't true. I can think of at least three other hypotheses that might explain my observation:
1. The California kids were better at using birth control.
2. Girls in California left school to have their babies.
3. Girls in California had more abortions.
Being the great big Data Geek that I am, I decided to look at the numbers. A little googling on "Teen Pregnancy" turned up rates for both pregnancies and live births in Arkansas and California in the 80's, and the numbers are pretty clear (click here for the data).
The most likely reason I didn't see any pregnant girls at my California high school is because they had abortions. I was hoping that maybe superior sex education in California would explain the difference, but it's very clear from the data that California kids got pregnant more than Arkansas kids. They just had fewer babies.
I'm writing about this not because I want to generate a discussion about the morality of abortion, but to marvel at the tools and data we all have available right at our fingertips to help us figure out whether or not what we believe is correct. A lot has changed since 1981-- including the teen pregnancy and abortion rates, which, happily, are WAY down from the 80's.