Five states and a Catholic hospital network are suing the Obama administration over a new rule requiring doctors to treat patients based on their gender identity instead of their biological sex.

The plaintiffs say the new regulation, finalized last month, would require doctors to perform gender transition surgeries on children even if they believe such surgery could be harmful.

If doctors refuse such surgeries, they could be subject to lawsuits, lost federal funding and investigation by the Health and Human Services Office of Civil Rights under the new rule, which adds "gender identity" to a nondiscrimination list in the Affordable Care Act.

The lawsuit is being filed Tuesday in federal district court in Wichita Falls, Texas, by the Becket Fund for Religious Liberty. That group is representing the Catholic hospital network Franciscan Alliance, the Christian Medical and Dental Associations and the states of Texas, Kansas, Kentucky, Nebraska and Wisconsin.

"No doctor should be forced to perform a procedure that he or she believes will harm a child," said Lori Windham, counsel for the Becket Fund. "Decisions on a child's medical treatment should be between families and their doctors, not dictated by politicians and government bureaucrats."

The plaintiffs are arguing that research shows that children, who are still in the process of forming their identity, can be harmed by hormones given to transition their biological sex. The Becket Fund has launched a website, transgendermandate.org, which says that as many as 94 percent of children with gender dysphoria grow out of the condition naturally and need no surgery or hormone treatment.

The website also argues that hormones to assist in sex reassignment cause an increased risk of heart disease, Type 2 diabetes and breast, ovarian and prostate cancer.

HHS first proposed the rule in May, on the same day President Obama issued an executive order requiring public schools to allow transgender students to use whichever bathroom they prefer, not the one assigned to their biological sex.