More than a dozen Chinese companies face legal action for allegedly asking job applicants to take pregnancy tests, reports CNN, citing state media. Prosecutors found that 168 women seeking positions at 16 companies in Nantong, a city in the eastern province of Jiangsu, had been tested illegally as part of their pre-employment physical check, the state-run Procuratorial Daily reported on Monday. The case highlights a contradiction at the heart of the Chinese economy: While the country is trying to boost record-low birth rates, some companies are reluctant to hire pregnant workers.

Employers have reportedly avoided recruiting women of childbearing age — with reports of women being asked about family planning during job interviews, or being passed over for roles even if they don’t plan to have children.

Chinese law bans employers from administering pregnancy tests or discriminating against pregnant workers.

In Nantong, authorities were tipped off by an online public litigation group, which said some employers in the city had given pregnancy tests to job seekers. Working with the group, prosecutors launched an investigation and visited two major public hospitals and a medical exam centre, according to the report.

At least one woman who was found to be expecting was not hired, the prosecutors said. The report didn’t name any of the companies nor specify whether any of them had been fined. According to Chinese law, companies can be fined up to 50,000 yuan ($6,900) for gender discrimination.