The American Civil Liberties Union (ACLU) and others piled onto the South Dakota legislature as it considered a bill that would make it a felony to provide things like puberty blockers to underage residents.

The bill targets doctors providing surgeries and other treatments in an effort to let children "mature" before making those decisions. “The changes are overwhelming and life-changing. Children need to wait until they’re mature to do it,” Rep. Fred Deutsch, the bill's sponsor, said. So far, the legislation has 40 co-sponsors and was scheduled for a committee hearing on Friday.

The prohibited interventions for the "purposes of attempting to change or affirm the minor's perception of the minor's sex, if that perception is inconsistent with the minor's sex." It would charge doctors with a Class 4 felony if they provided a long list of surgeries like "castration, vasectomy, hysterectomy, phalloplasty," and others. Mastectomies are also banned, in addition to "removing any otherwise healthy or nondiseased body part or tissue." The proposed law would not apply to children born with ambiguous or conflicting genitalia.

Progressive advocates sounded the alarm in response to Deutsch's legislation. "The time to act is now," the ACLU of South Dakota tweeted. It followed with a long list of legislator's home and office numbers.

ACLU SUING OVER IOWA'S DECISION TO ALLOW RESTRICTIONS ON TAXPAYER FUNDING OF GENDER SURGERIES

“(Transgender) kids and families should be given the opportunity to thrive in South Dakota,” Libby Skarin, policy director for the ACLU of South, said in a statement. “This legislation only stands to harm them and make their lives harder.”

The issue even caught actress Debra Messing's attention as she retweeted a message about the law. "URGENT," she said.

ACLU CLAIMS 'MEN WHO GET PREGNANT AND GIVE BIRTH ARE MEN'

Democratic legislative leaders said they would oppose the bill. Rep. Kelly Sullivan, a Sioux Falls Democrat, said the measure would interfere in the doctor-patient relationship, and that doctors, patients and families should make decisions for treatment. GOP Gov. Kristi Noem's office declined to comment. "The governor does not comment on draft legislation," press secretary Kristin Wileman told Fox News.

Conservative lawmakers in several states including Texas, Georgia and Kentucky have introduced similar bills. Deutsch said he decided to introduce the bill after reading about the issue online. He also consulted with a group called Kelsey Coalition that opposes those types of operations for minors.

The legislation seemed to fan flames surrounding the role of government in a broader, cultural movement on gender. Conservatives like Ryan T. Anderson of the Heritage Foundation have warned against medical interventions that could alter a minor's development.

CLICK HERE TO GE THE FOX NEWS APP

"Prudent legislation is needed to prevent adults from interfering with a child’s normal, natural bodily development," Anderson and Princeton professor Robert P. George wrote in December. "'Gender affirmation' procedures violate sound medical ethics. It is profoundly unethical to intervene in the normal physical development of a child as part of 'affirming' a 'gender identity' at odds with bodily sex," they added.

The Endocrine Society, which is the leading professional organization for doctors who specialize in hormones, does not recommend these types of treatments before puberty for children who do not identify with their biological gender. For youths experiencing puberty and older adolescents, the Endocrine Society recommends that a team composed of expert medical professionals and mental health professionals manages treatment.

The Associated Press contributed to this report.