The Coalition on Abortion/Breast Cancer notes that an Armenian study-whose authors examined diabetes mellitus type 2, reproductive factors, and breast cancer-found a statistically significant association showing a 2.86-fold increased breast cancer risk from one induced abortion.  The study, led by Lilit Khachatryan, included researchers from Johns Hopkins School of Public Health and the University of Pennsylvania.
Khachatryan’s team reported a statistically significant 13% increased breast cancer risk for every one year delay of a first full term pregnancy (FFTP), with delayed FFTPs until ages 21-30 or after age 30 resulting in 2.21-fold and 4.95-fold increased risks respectively, as opposed to women with FFTPs before age 20. (Abortion is often used to delay FFTPs.) Giving birth resulted in a 64% reduced risk.
Due to political correctness, the authors also inaccurately claimed, “Most evidence (of an abortion-breast cancer link)…points to no effect.” Professor Joel Brind (Baruch College, City University of New York) said that is “plainly false.” 
Fifty-one of 68 epidemiological studies since 1957 report an abortion-breast cancer (ABC) link (not counting biological and experimental evidence).
Khachatryan’s team cited only one (severely criticized) study, Melbye et al. 1997, to support their false claim of “no effect.” [3,4,5] Although Melbye’s team found no overall increased risk, they reported a statistically significant 89% increased risk for those having abortions after 18 weeks gestation…. (Source)