From left, filmmaker Lana Wilson, Dr. Susan Robinson, Dr. LeRoy Carhart, and filmmaker Martha Shane from the documentary "After Tiller" pose for a portrait during the 2013 Sundance Film Festival at the Fender Music Lodge, on Friday, Jan. 18, 2013 in Park City, Utah. (Photo by Victoria Will/Invision/AP Images)
Doctors Susan Robinson, left, and LeRoy Carhart from the documentary "After Tiller" pose for a portrait during the 2013 Sundance Film Festival at the Fender Music Lodge, on Friday, Jan. 18, 2013 in Park City, Utah. (Photo by Victoria Will/Invision/AP Images)
Doctor Susan Robinson from the documentary "After Tiller" poses for a portrait during the 2013 Sundance Film Festival at the Fender Music Lodge, on Friday, Jan. 18, 2013 in Park City, Utah. (Photo by Victoria Will/Invision/AP Images)
PARK CITY, Utah (AP) — Third-trimester abortions — those done beyond the 28th week of pregnancy — account for less than 1 percent of all abortions performed in the United States each year. Only four doctors nationwide offer the procedure. Their stories and those of …