GEORGE BALANCHINE STRONGLY disapproved when his ballerinas got pregnant. He wanted them dancing, not nursing. But in the past 40 years, women have learned to balance motherhood and their professional lives – though dancers, like athletes, still have particularly difficult choices to make. Kirstin E. Williams's all-female Strong Current Dance Company has long looked at women's issues through a particularly feminist eye. So it should come as no surprise that Quiet Pressure examines the "nuanced silence" that surrounds mothers. Have we maybe come so far that certain aspects of being female make us slightly uncomfortable? Yet, Williams appears to tell us with this program, some of the biggest proponents for social change are mothers who don't want their children to grow up homeless or impoverished (depicted by a work incorporating the art and poetry of the Berkeley-based Sisters Project), to be in danger of spending their lives in jail (illustrated by Behind the Faces and Inside, featuring hip-hop dancers from City College of San Francisco), or to be shipped off to war (explored in the Pieces of Mind installation). The evening concludes with Bleeding Heart, a work that just may restore the term to its original meaning. 8 p.m., 3153 17th St., S.F. $18-$20. (415) 863-9834. (Rita Felciano)