TIANJIN, China — Bella Wang barely noticed the section on the application inquiring whether she was married or had children. Employers in China routinely ask women such questions, and she had encountered them before in job interviews.

It was a surprise, though, after she accepted a position as a manager at the company, a big language-training business in the northern city of Tianjin, when she was told the job came with a condition.

As a married woman without children, she would have to sign a “special agreement” promising not to get pregnant for two years. If she broke that promise, the company said, she could be fired, without compensation.

Ms. Wang, 32, fluent in English with a degree in international trade, was outraged — but she signed.