SANTIAGO, Chile — Karen Espíndola was 22 and 12 weeks pregnant when a doctor told her that her baby was doomed to die. It suffered from a malformation that prevents the normal development of the brain.

It would not survive long, if at all.

The fraught debate over Chile’s abortion ban, which may be partly lifted on Friday, wasn’t one of Ms. Espíndola’s concerns that day in August 2008. Although she had just broken up with her boyfriend, who refused to acknowledge paternity, she had decided to wing it as a single mother. She had a stable job at an insurance company, her parents were supportive and she began dreaming about her future child, and what they would do together.

After learning about the condition, holoprosencephaly, or HPE, online, Ms. Espíndola asked her doctor for an abortion. It was a painful decision, but there was nothing science or God could do, she concluded. Why go through a treacherous nine months only to have the child suffer and die?

The doctor said that was not possible.

Ms. Espíndola, now a 31-year-old psychology student, knew abortion was illegal in Chile, but assumed it was allowed under dire circumstances. Ms. Espíndola imagined her son with the severe facial malformations typical of HPE, or giving a stillbirth. She had trouble sleeping and eating and lost 26 pounds. She stopped going to work and withdrew from the world.