A couple filed a lawsuit Tuesday against the state of South Carolina for what they say was an unnecessary sexual assignment surgery performed on a toddler they later adopted.

Lawyers for Pam and Mark Crawford said Tuesday they were suing the Department of Social Services for having irreversible surgery performed on a 16-month-old child they eventually adopted and raised as a girl.

The child was born in 2004 with both male and female genitalia and placed in state custody after the termination of parental rights, according court papers. At the age of 16 months, doctors removed the child's male genitalia, leaving the toddler with female parts, according to court papers.

"The doctors knew that sex assignment surgeries on infants ... poses a significant risk of imposing a gender that is ultimately rejected by the patient," attorneys claim in the suit.

Instead, the lawyers argue, the optional surgery should have been delayed until the child was older and identified as male or female.

"That was a permanent, irreversible decision that was not theirs to make," attorney Ken Suggs said Tuesday of the lawsuits, which he said are the first of their kind in the U.S.

At the time of adoption, the Crawfords said they knew their child was born with ambiguous genitalia and raised the child as a girl starting in 2006. But about a year ago, the Crawfords say their now-8-year-old child told them he wanted to be raised as a boy. They supported the decision, allowing him to cut his hair short and wear boys' clothes.

The Crawfords said their family is adjusting, their son is happy and has the support of his community and school. But they chose to sue to keep other families from going through similar struggles.

"He keeps us smiling, but it's heartbreaking when he asks us questions about his body," Mark Crawford said. "We don't want him to become bitter."

The state lawsuit accuses the Medical University of South Carolina — where the surgery was performed — and Greenville Hospital — where the child was born — of negligence medical malpractice for not getting the patient's informed consent before surgery and failing to warn of potential problems resulting from it. At 16 months old, the suit alleges, the child was too young to make such a decision, one that could have waited until years later.

That complaint accuses state Social Services officials of failing to protect the child from the consequences of the surgery. A federal lawsuit also accuses doctors and state officials of violating the child's civil rights by performing the surgery without consent.

A spokeswoman for the Greenville Hospital System did not immediately comment on the suit. The Medical University of South Carolina and the Department of Social Services declined to comment.

The child is healthy, but the Crawfords' lawyers say there are medical issues that can result from the surgery, including sterilization or the loss of sexual function.

"These doctors wanted to play God," said Alesdair Ittelson, an attorney with the Southern Poverty Law Center, which helped bring the lawsuit. About one in every 2,000 children is born "intersex," or with ambiguous genitalia, according to Anne Tamar-Mattis, an attorney with Advocates for Informed Choice, a group that supports intersex children.

Dr. Margaret Moon, a pediatrician who teaches at the Johns Hopkins Berman Institute of Bioethics, said while it might be easier on a family to have such surgeries performed when a child is young, ultimately it's best to wait until the child's own gender identity begins to develop.

"We know that it's probably better to wait and let the child make some choices, but it's at a cost to the family," Moon said. "The sadness of this child was that he was physically forced in to a gender that sort of didn't fit. ... He's going to have a hard time."