SEOUL, South Korea — Lee Na-yeon was 18 years old and in her first semester in college when she discovered, to her dismay, that she was pregnant.

Ms. Lee went to a hospital and had an abortion. But as a graduate of a Catholic high school where she had been shown graphic videos portraying abortion as murder, she felt scared and tormented by guilt.

She had also broken the law.

Abortion is illegal in South Korea with just a few exceptions, such as when a woman has been raped or her health is at risk. It is one of just a handful of the world’s richest countries to have such restrictive abortion laws. Women can be sentenced to a year in prison or ordered to pay fines of two million won (about $1,840) for having abortions, while doctors who perform them can get up to two years in prison.

Now, a group of women’s advocates is pushing to overturn the ban, and the country’s Constitutional Court is set this year to review a case that challenges the law’s constitutionality.