A terminally ill woman in the US state of Indiana and her wife have joined a lawsuit to demand that the state recognise their marriage.

The couple, Amy Sandler and Niki Quasney married in Massachusetts, and who live in Munster, are requesting that the state immediately recognise their marriage.

They join Baskin et al v Bogan et al, which is one of five lawsuits filed in federal court seeking to challenge the state’s refusal to perform same-sex marriages or recognise out-of-state marriages.

Quasney has ovarian cancer, was diagnosed in 2009, and the couple hope to be able to access state and federal help for surviving spouses and children.

“This family shouldn’t have to endure discrimination from the state of Indiana while fighting to enjoy the time they have left together as a family dealing with a terminal illness,” said Paul Castillo, staff attorney for Lambda Legal, in a statement.

A spokesman for Lambda Legal said the judge could issue an order to recognise the marriage as early as Wednesday, rather than waiting for a ruling.