Ashfield District Council is being urged to provide more support for female councillors who are going on maternity leave.
Gender equality charity the Fawcett Society said equal representation in councils is vital, as decisions made by local government have a "disproportionate impact" on women's lives.
A 2017 report carried out by the charity with the Local Government Information Unit think tank, called for the introduction of maternity rights at all councils to make them more accessible for women.
But new research by the Fawcett Society has found that Ashfield District Council is one of almost 250 local authorities that has yet to introduce any.
Council rules for England state that if a councillor fails to attend meetings for six months, they can be sacked from the council.
This means that if female councillors take the 12 months' maternity leave they would be entitled to in other jobs, they could lose their position.
The Fawcett Society says this is partly to blame for the lack of diversity in councils.
Ashfield District Council is one of the most male-dominated local authorities in England, with just seven of its 35 council seats won by women in May's election - or 20 per cent.
But the council has defended itself and said councillors will have the "opportunity" to consider the issue later this year.
Rob Mitchell, council chief executive, said: “We will have an opportunity to consider these issues later this year via an Independent Remuneration Panel, who make recommendations to councils on Members Allowance Scheme.
“The six month attendance rule is statutory and is not something we control or can change. After six months the councillor becomes legally disqualified.
"There is legal provision for the council to consider an exemption to this. This is the approach we would be likely take in case of maternity leave.
"We have not experienced a councillor seeking maternity leave and so it is not something the council has yet had to consider.
“Ashfield District Council is proud to have an employee gender pay gap of only 0.45 per cent. The number of female councillors is determined through a democratic process.”