So you all know I'm a number nerd. And with all the heated debate on my post, I wanted to see the numbers (because in my mind, numbers don't lie ;) ). I was genuinely curious after reading all the links and quotes from this study and that study if the numbers matched up to the claim that contraceptive reduced or increased the rate of abortion. After reading some of the studies from Guttmacher, I though for sure it would show in favor of contraceptives lowering the abortion rate among women of child-bearing age. So here goes...
I had a hard time finding use rates of contraceptives among women of child-bearing age (15-49), but I found it for four years. Then I found how many women there were of child-bearing age that year and the number of abortions performed that year. Here's the numbers. You can make your own conclusions, or you can read mine. I cited the sources for my numbers below as well, so feel free to double check. I used LibreOffice Calc to automatically calculate the percent of women who had an abortion, but feel free to double check those numbers if you wish as well.
While I hated statistics in college, I'm seeing that from the numbers I found, every year, except the first year that abortion was legalized, that the higher the rate of the use of contraceptive, the higher the rate of abortion among women of child-bearing age. So my conclusion would be that yes, in fact, higher contraceptive use correlates with a higher abortion rate.
Abortions per year: http://www.johnstonsarchive.net/policy/abortion/graphusabrate.html (They pulled their abortion numbers from a couple places on http://www.guttmacher.org/. I used them because it had it all in one place versus several different pages)
Population of Women of Child-bearing Age 1973, 1976: http://www.cdc.gov/nchs/data/statab/pop6097.pdf
Population of Women of Child-bearing Age 1995: http://www.census.gov/popest/data/national/totals/1990s/tables/nat-agesex.txt
Population of Women of Child-bearing Age 2006: https://www.census.gov/population/age/data/2006comp.html Table 1.1
Percent of Women using Contraceptives 1973, 1976: http://www.cdc.gov/nchs/data/series/sr_23/sr23_010.pdf
Percent of Women using Contraceptives 1995, 2006: http://www.cdc.gov/nchs/data/series/sr_23/sr23_029.pdf