Christian conservative group Liberty Counsel argues in a brief in support of Michigan's gay marriage ban that allowing gay couples to marry will increase sexually transmitted diseases in the state.

In its 39-page brief, the Christian law firm headed by Mat Staver, a vocal opponent of LGBT rights, claims there are “inherent harms associated with same-sex unions.”

“The nature of the sexual acts in which same-sex couples engage carry health risks that are not as prevalent, or in some cases, not present at all, in heterosexual individuals,” the document states.

After conducting a two-week trial in March, a federal judge struck down Michigan's ban as unconstitutional.

State officials asked the Sixth Circuit Court of Appeals in Cincinnati to review the order.

In its amicus brief, Liberty Counsel argues that “homosexual males are at exponentially higher risk of developing a variety of sexually transmitted diseases, and have increased risks of developing various cancers and medical conditions because of the nature of same sex.”

“It would be rational for the voters of Michigan to seek to minimize the deleterious effects of these conditions on public health, safety and welfare by affirming that marriage in Michigan remains the union of one man and one woman.”

A spokeswoman for the group told Think Progress' Zack Ford that it believes the ban discourages gay sex.

Ford noted that researchers have found that health inequities among the LGBT population are “related to the discrimination and stigma against homosexuality.”

Ford cited several studies, including one which found that marriage equality increases the mental and physical well being of gay couples.