SAN SALVADOR — When Teodora del Carmen Vásquez walked out of the Ilopango women’s prison a few weeks ago, she embraced her parents, her teenage son — and a movement to change an anti-abortion law that stole more than a decade of her life.

In El Salvador, where a total ban on abortion leads to an immediate suspicion of women whose pregnancies do not end with a healthy baby, Ms. Vásquez was marked as a criminal after she began bleeding and suffered a stillbirth. Sentenced to 30 years for aggravated homicide, she was released only after the Supreme Court ruled that there was not enough evidence to show she had killed her baby.

“This is the moment to speak out, this is the moment to act,” said Ms. Vásquez, who was the spokeswoman in prison for a group of two dozen women accused as she was. “With the situation we’re in now, in a few years it will be a crime to be a woman in El Salvador.”