Avril Lavigne sang at the “Volvo for Life” awards ceremony in NY yesterday. Her tummy looked less than flat in a tight top with horizontal black stripes.

The awards honored young people who do extraordinary volunteer work “in the areas of safety, quality of life and environment.” They were hosted by Benjamin Bratt, with performances by Avril Lavigne and the Harlem Gospel Choir.

Lavigne, 21, is rumored to be pregnant. She has been engaged to Sum 41 frontman Deryck Whibley, 25, since June 2005 and owns a home with him in Beverly Hills. She has recently said that she wants to marry Whibley this summer and plans to have children.

Pictures [via]