TOKYO (AP) — Women's rights activists in Japan renewed their demand Wednesday for the government to allow married couples the option to keep both of their surnames, saying the current practice in which most women face social pressure to adopt their husbands' surnames — a prewar tradition based on paternalistic family values — widens gender inequality.

At a rally marking International Women's Day, representatives from dozens of women's rights groups delivered a joint statement to lawmakers urging them to do more to change the 125-year-old civil code, which forces married couples to choose one surname.

“We strongly urge the parliament to face the issue and promptly achieve a revision to the civil code,” the activists said in a statement they handed to lawmakers who also attended the rally in Tokyo.

Public support for a dual-surname option has grown, with surveys showing a majority now supports the option for married couples to keep separate surnames. Some couples have also brought lawsuits saying the current law violates the constitutional guarantee of gender equality since women almost always sacrifice their surnames.

Under the 1898 civil code, a couple must adopt “the surname of the husband or wife” at the time of marriage — which experts say is the only such legislation in the world. Although the law does not specify which name, 95% of women adopt their husbands’ surnames, as paternalistic family values persist and women are generally seen as marrying into their husband's household.

A 1996 government panel recommendation that would allow couples the option to keep separate surnames has been shelved for nearly three decades due to opposition by the governing Liberal Democratic Party.

Prime Minister Fumio Kishida’s conservative governing party faces growing calls to allow more diversity in family values and marriage. Many in his Liberal Democratic Party support traditional gender roles and a paternalistic family system, arguing that allowing the option of separate surnames would destroy family unity and affect children.

Rally organizer Yoko Sakamoto, a long-time activist calling for the change, said it’s time to push harder. “We should even think about not voting for candidates who oppose the change in next elections,” she said.

Activists say the one-surname requirement almost always forces women to compromise and go through the trouble of changing their names in official documents and identification cards at work or elsewhere.

As more women pursue careers, a growing number want to keep using their maiden names at work, while using their registered surnames in legal documents. Some companies and government offices now allow female employees to use their maiden names at work, but they are a minority and the measure is voluntary.

Because of outdated social and legal systems surrounding family issues, younger Japanese are increasingly reluctant to get married and have children, contributing to a low birthrate and shrinking population. Some experts say Japan’s one-surname-only policy is among the reasons women hesitate to get married.

A 2015 Supreme Court ruling urged parliament to discuss the surname issue instead of issuing a legal judgement, but parliamentary deliberation has stalled amid opposition by conservative members of the governing party.

The rights gap between men and women in Japan is among the world’s largest. Japan ranked 116th in a 146-nation survey by the World Economic Forum for 2022 that measured progress toward gender equality based on economic and political participation, as well as education, health and other opportunities for women.