The councillor in charge of Birmingham's children's services was told she would probably have to step down if she became pregnant - because the council has no maternity policy.
Brigid Jones, cabinet member for education and social services, said she was told a procedure did not exist for someone in her role.
Ms Jones, a councillor since 2011, branded the situation "ridiculous".
Birmingham City Council said it was looking at introducing a policy.
Ms Jones, who was 26 years old when appointed to the council's cabinet in 2013, said she was thinking about starting a family and had enquired about her rights.
The Labour councillor said she was told there was no provision for maternity arrangements attached to her £41,696.75 a year job.
"I was told there isn't a policy and I'd most likely have to step down from my position if I were to have a child," she said.
"Obviously I thought this was ridiculous. I talked to the chief executive [Mark Rogers] and he thought it was ridiculous. He's now working on a policy."
Ms Jones, a councillor for the Selly Oak Ward, said she also felt that "the job of a councillor is from the dark ages."