2. Almost everyone uses contraception, including 98% of Catholic women.
This one makes me so mad. As soon as I heard this statistic, I searched for the research results and concluded that it is horrendously misrepresented and skewed.
A summary of how they came to this number: Of women who claim they are Catholic on a phone survey aged between 15-44 who are sexually active, not pregnant, not trying to become pregnant, not postpartum, not actively trying to avoid pregnancy, and not naturally or for medical purposes sterile, 98% have used some form of contraception. Including the method we call 'no method.'
So..........
To put this another way, if we exclude all of the women who don't use birth control, 98% of the remaining women use birth control. The other 2% use NFP. Go figure.
Here is an excellent analysis of the statistics from "The Truthiness Will Set You Free." I've been meaning to do my own, but this is too perfect to pass up.
Interested in the original results of the study? Here and here.
Edit:
I just found this great study from familyplanning.net:
http://familiadelasamericas.org/inc/data/divorce_study_eng_wilson.pdf
It actually addresses many of the same topics discussed in the Guttmacher studies, but (obviously) with a different bias. They include results from their own study and results from the National Survey of Family Growth, carried out by the US Government's National Center for Health Statistics.