The Orphan's Tale by Pam Jenoff

During World War II a Dutch girl, Noa, is impregnated by a German soldier.  Thrown out of her home by her father she is forced to give up her baby and finds work cleaning in a rail station.  Discovering a boxcar full of Jewish babies, many of them dead, she snatches a live baby and flees into the cold, snowy night. Noa is rescued by a circus performer and eventually becomes part of a German circus as an aerialist. Though not welcomed at first by Astrid, a superb acrobat who is forced to train her, a great friendship develops between the two women. Astrid has secrets and has found refuge in the circus.  The circus travels and puts on many performances but dangers abound even as people flock to the circus for entertainment and relief from the oppression of war. The story of these two women and other characters in this book is a historical novel of sacrifice and survival, one that sticks in my memory and I enjoyed.