I think three crucial factors around the abortion rate are:
A. Reduction of unwanted pregnancies (frank sexual education instilling respect-consent, shame free, no cost access to pills at request, no male dominance hindering the use of condoms, etc)
B. Support without hurdles for availability clinics, financials and guilt/shame (money, compassion, respect, culture).
C. Country/ethnicity culture
A. The teen pregnancy rate (60 per 1,000 for 15-19 year old) in the US is very high compared to other OECD countries and fortunately decreasing over time.
I think it is fair to conclude that there is a lot to gain by good sexual education programs doing more than just the mechanical technics.
On the impact of such a teen pregnancy. The US pregnancy rate for 15-19 was in 2014 just below 60 per 1,000. That means 5*60 per 1,000 for that 5 year period, or 3 in 10 teenagers get pregnant.
B. Most has already been said in earlier posts. Not that much to add than that I believe that the money needed to give a pregnant woman her own choice without external hurdles, is not only right and good for that woman, but also beneficial for the good of all.
C. The country/ethnicity culture has such a big effect on the statistics, that any reduction policy, program or package of available means, needs to understands the why's of those differences to be effective.
In my country, from 2008 national statistics, the abortion rate of autochtones is about 5 per 1,000. The abortion rate of the first and second generation Turkish and Moroccan women is around 15 per 1,000. For 1th-2nd generation Surinam women the rate is 32 per 1,000 (Afro-Surinams and Surinam people originally from India). For 1th-2nd generation Antillian women the rate is 39 per 1,000 (Afro-Antillians).
You could argue this is from economical differences, but our wellfare country, including a National Health Care, no-hurdle access to everybody and everything around anti-conception-abortus, is of too high level to explain those big differences in abortion rate.
Teen pregnancy rates in my countyry have a similar difference per ethnicity. The average for all groups being 12 per 1,000 resulting in 7 per 1,000 teen abortions and 5 per 1,000 teen births.
=> in your policies and programs you need to differentiate for your different target profiles.