ST. LOUIS (AP) — A transgender inmate is suing the Missouri prison system for refusing to provide hormone therapy as she transitions to a woman, adding her voice to those of prisoners in other states who argue that denying such treatment amounts to cruel and unusual punishment.

Lambda Legal filed the lawsuit in federal court in St. Louis last week on behalf of Jessica Hicklin, a 37-year old inmate serving life in prison after being convicted of first-degree murder at age 16, when she went by her birth name, James. She is challenging a state Department of Corrections policy that bars hormone therapy for inmates who weren’t receiving it before being incarcerated.

According to her lawsuit, it wasn’t until last year that medical experts determined that Hicklin has gender dysphoria, in which a person feels extreme distress because of a disconnect between their birth sex and gender identity. But in a blog posted on Lambda Legal’s website, Hicklin wrote that she felt she was a girl since she was very young.

“Even at 16, I felt I was on my way to certain death. I didn’t know what gender dysphoria was, or how to explain my feelings to my family or others in my small town,” wrote Hicklin, who was convicted of fatally shooting a man during a drug-related crime in the small town of Clinton in 1995.

The lawsuit contends that experts advised she undergo hormone therapy and permanent hair removal and that she have access to “gender-affirming” products from the prison commissary store that typically aren’t available at the all-male Potosi Correctional Center where she’s imprisoned. It also says she’s been sexually assaulted in prison and has anxiety and depression, along with “intrusive thoughts” of cutting off her own testicles because of the denied treatment.

In her blog posting, Hicklin wrote that she feels “locked in a prison within a prison — my body.”

“This personal prison is much crueler, and without a change in policy, I’m not sure I will survive it,” she wrote.

Missouri Department of Corrections spokesman David Owen and Martha Harbin, a spokeswoman for Corizon Health, which provides health care for the prison system and is also named in the lawsuit, declined to comment, citing pending litigation.

The Bureau of Justice Statistics estimates that there are 3,200 transgender inmates in the nation’s prisons and jails.

Federal inmates can receive treatment for gender dysphoria if an evaluation determines they need it, based on a policy enacted in 2011. The policy applies whether therapy was prescribed before or after the inmate entered federal custody.

But states continue to have varying regulations.

“It’s a hard battle that Jessica and others in her situation have to face, when they have to explain to a state why they need medical treatment,” said Richard Saenz, an attorney for Lambda Legal, a Washington-based non-profit for lesbians, gay, bisexual and transgender people and those with HIV and AIDS.

Last year, the U.S. Department of Justice wrote in a court filing that state prison officials must treat an inmate’s gender identity condition just as they would treat other medical or mental health conditions, regardless of when the diagnosis occurred. The filing was part of a lawsuit on behalf of Ashley Diamond, a transgender woman who was imprisoned at the time in Georgia.

Diamond has since been paroled. In February, Georgia agreed to pay $250,000 to settle her lawsuit.

W. John Thomas, a health law expert at Quinnipiac University’s schools of law and medicine, said prison systems are facing increasing pressure to tend to the medical needs of transgender inmates and that he thinks the issue will likely make its way to the U.S. Supreme Court. He said state corrections departments often oppose treatment for transgender inmates for two reasons: the cost and the “political and moralistic.”

A lawsuit similar to Hicklin’s was filed earlier this month by Reiyn Keohane, a transgender Florida prisoner who is seeking hormone treatments.

In June, a federal judge ruled that California must allow transgender inmates to have more female-oriented commissary items like nightgowns and necklaces. The ruling was part of a settlement that will make California the first state to pay for an inmate’s sex reassignment surgery.

In December, an 8th U.S. Circuit Court of Appeals panel rejected an Arkansas inmate’s appeal seeking gender reassignment hormones to transition to a woman. It ruled that several mental health professionals evaluated Andrew Reid, who identified as a woman, and had not diagnosed a gender identity disorder.

Perhaps the most well-known case of a transgender prisoner seeking treatment was that of Chelsea Manning, the former Army intelligence analyst serving a 35-year sentence at a military prison for leaking government documents to Wikileaks. Last year, the Army agreed to pay for hormone treatments for Manning, who was previously known as Bradley.

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