The activists stood outside the parliament building in Croatia's capital, Zagreb, demanding that authorities help Miranda Cavajda and ensure abortion rights are respected in the socially conservative country.
Cavajda was 20 weeks pregnant when doctors informed her that her fetus had a brain tumor and no chance of a normal life. She said doctors refused to terminate the pregnancy and advised Cavajda to seek the procedure in neighboring Slovenia instead.
A medical ethics commission is reviewing Cavajda's case. Croatian media reported that doctors said there were unsure of the procedural regulations for ending such an advanced pregnancy.
The existing law that permits abortions dates back to 1978, when the country was part of the Communist-run former Yugoslavia. Croatia became an independent country in 1991, and since then increasingly influential conservative groups have tried to get abortion banned.
President Zoran Milanovic on Wednesday described Cavajda's ordeal as an example of “conservative regression.”
Activists at Friday's demonstration demanded punishment for the medical professionals who denied Cavajda an abortion. An open letter read at the protest said her situation “is the fight of every woman.”
“We are sorry we live in a state which puts someone's beliefs before the dignity, health and life of women and children,” the letter read. “We stand here united in solidarity.”