COLUMBUS (AP) — A lawsuit recently filed in Ohio is demanding the state stop collecting sales tax on feminine hygiene products because it says the tax discriminates against women.

The suit seeking class-action status was filed in the Ohio Court of Claims against the state on behalf of four Cleveland-area women who argue the tax on products including tampons violates equal protection clauses of the U.S. and Ohio Constitutions.

“It really is unequal protection and discriminatory,” said Sandra Kelly, a Cleveland lawyer involved in the lawsuit. “I can’t imagine something else that is medically necessary for women that is taxed.”

The complaint argues that with women spending an average of approximately $70 per year on feminine hygiene products, “a tax on tampons and pads is a tax on women.” The suit estimates that the state brings in $11 million annually by taxing the products. It seeks to refund at least $66 million to female consumers across Ohio.

Rep. Greta Johnson, an Akron Democrat, called the products “a medical necessity — not a luxury item.” Many medical items are untaxed in the state.

Two bills are currently circulating in the House of Representatives that would end the tax. One of the bills also seeks to add non-prescription drugs and disposable baby diapers to the list of products exempt from the sales tax.

“I have to tell you, I have no idea why states would tax these as luxury items,” President Barack Obama said of the “tampon tax” earlier this year. “I suspect it’s because men were making the laws when those taxes were passed.”

The defendant, the Ohio Department of Taxation, declined to comment on pending litigation.