Alone -- many of them never nurtured themselves -- the pregnant inner-city Chicago teenagers in the gripping documentary A DOULA STORY face terrible odds. Their champion is a former teenage mother herself, Loretha Weisinger. As a doula, the Greek word for birth attendant, Weisinger helps her young charges prepare for motherhood, labor and the long road ahead in director Daniel Alpert's awe-inspiring portrait of this guardian angel and superwoman. Free. May 18. 7:30 p.m. Martin Luther King Jr. National Historic Site Screening Room, 450 Auburn Ave. 404-331-5190. www.imagefv.org.