The government is being taken to court over claims its Covid-19 financial support scheme discriminates against women who have had babies recently.

The Pregnant Then Screwed charity say that around 75,000 self-employed women who have taken maternity leave in the last few years are getting less help than those who have not.

The Covid-19 Self Employed Income Support Scheme (SEISS) was introduced in March last year alongside the furlough scheme.

Payments are calculated on average profits made between 2016 and 2019, meaning tens of thousands of women are estimated to have lost out on a proportion of the money.

Campaigners say that maternity leave should not be treated as "time off" or as a "holiday", but as work "integral" to a "well-functioning" society.

A judicial review is being brought against the government on Thursday for indirect sexual discrimination.

Joeli Brearley, founder of Pregnant Then Screwed, wants periods of maternity leave to be exempt from calculations and for women affected to be given a rebate.

"In (the government's) legal letter they correlated maternity leave to being the same as a sabbatical or sick leave," she said.

"What is particularly disappointing to these women is that they feel the role that they have played for perhaps a year of raising a new human, and all the work that that entails, is not valued at all by the government and by society."

"This court case is about defending women's rights and showing the government that they cannot ride roughshod over the Equality Act," she added.

Particular concern is also being raised for single self-employed mothers who are struggling "to put food on the table" and "keep a roof over their head".

Cara Bowen went on maternity leave between 2018 and 2019, which brought her three-year average income down "significantly".

While "glad" to be receiving any grant, her male counterparts "in a similar position" have qualified for higher payments.

"I have undoubtedly been penalised for having a child," she told Sky News. "Maternity leave is not a holiday or sick leave, it is totally accounted for and the government know exactly why my income was lower for one year.

"They should easily be able to take this into account. I've constantly been made to feel like a second class citizen, both as a self-employed person and as a woman trying to make ends meet, and it's simply not fair to be penalised for something that only mothers have to go through.

"Perhaps I would feel differently if men were able to claim Paternity Allowance as self-employed but they can't (and that's a problem in itself), so therefore it is clear that this pure discrimination against working mothers."

The Treasury has in the past described SEISS as one of the "most generous" schemes of its kind in the world.

When asked to comment on the campaign, an HM Treasury spokesperson said: "We have submitted our arguments to the court this week on the Motherhood Judicial Review, ahead of the hearing on January 21.

"We cannot comment further on ongoing litigation."