Prosecutors in Alabama said on Wednesday that they were dropping a manslaughter charge against a woman over the death of the fetus she was carrying when she was shot in the belly, in a case that stirred national outrage.

The woman, Marshae Jones, was accused of beating up a co-worker who ultimately drew a gun and fired it, wounding Ms. Jones in the stomach and killing her five-month-old fetus. A grand jury in Jefferson County, convened by District Attorney Lynneice Washington, dismissed charges against the co-worker, saying she had acted in self-defense. But it indicted Ms. Jones for “initiating a fight knowing she was five months pregnant.”

Under Alabama law, a fetus is considered to have the same rights as a child who has already been born. The grand jury sought to hold someone accountable for its death and Ms. Jones was arrested last week. The charges against her quickly drew national attention.

On Wednesday, Ms. Washington, who had signed the indictment, said in a brief news conference that she had weighed the evidence and decided to dismiss the case.