A same-sex couple became the first in the US state of Illinois to marry, as a judge ruled they should be granted a marriage licence six months early as one of them has terminal cancer.

US district judge Thomas Durkin on Monday ordered the Cook County clerk to issue an expedited marriage license to Chicago couple Vernita Gray and Patricia Ewert.

Illinois Governor Pat Quinn signed the state’s equal marriage bill into law earlier this month, although weddings are not set to take place until June 1, 2014.

Ms Gray is currently terminally ill with cancer, which has spread to her bones and brain. Doctors have told her she is not expected to live until June.

The couple married in a private ceremony on Wednesday just days after Judge Durkin’s ruling.

“This is the realization of a very long cherished dream for them both,” Camilla Taylor, the head of Lambda Legal, which helped represent the couple, said before the ceremony.

Continuing, she said it means that Ms Ewert will be better protected by benefits related to marriage, but not civil unions.

Human rights advocates have speculated that this case may be the beginning of efforts to bring forward the effective date of the law signed by Governor Quinn.

He has said he would sign a bill to change the date if it came to his desk. “The sooner the better”, he said.