WASHINGTON — Amy Brenneman, an actress, wants Justice Anthony M. Kennedy to know about the abortion she had when she was a 21-year-old college junior.

Taking a page from the movement for same-sex marriage, Ms. Brenneman and more than 100 other women have filed several supporting briefs in a major Supreme Court abortion case to be argued on Wednesday. The briefs tell the stories of women who say their abortions allowed them to control their bodies, plan for the future and welcome children into their lives when their careers were established and their personal lives were on solid ground.

The briefs are aimed largely at Justice Kennedy, who holds the crucial vote in abortion cases. They use language and concepts from his four major gay rights decisions, notably his invocation of “equal dignity” in June’s ruling establishing a constitutional right to same-sex marriage.

“Why has marriage equality gained so much ground, and reproductive justice seems to be losing so much ground?” Ms. Brenneman, known for her roles on “NYPD Blue” and “Judging Amy,” said in an interview. Partly, she said, because gay couples have come out of the shadows but many women still believe abortions to be shameful secrets.