A convicted murderer who strangled an expectant mother in Missouri and cut the baby from her womb 16 years ago, became the first woman in nearly seven decades to be federally executed early Wednesday.

Lisa Montgomery’s execution came after the U.S. Supreme Court denied an effort by her defense attorneys to stay her execution based on her ability to understand her death sentence.

Montgomery, 52, was pronounced dead at 1:31 a.m. Wednesday after receiving a lethal injection at the federal prison complex in Terre Haute, Indiana. She was the 11th prisoner to receive a lethal injection there since July when President Trump, an ardent supporter of capital punishment, resumed federal executions following 17 years without one.

She was the first of the final three federal inmates scheduled to die before next week’s inauguration of President-elect Joe Biden, who is expected to discontinue federal executions.

Kelley Henry, Montgomery’s attorney, blamed the Trump administration’s "bloodlust" for her execution.

"The craven bloodlust of a failed administration was on full display tonight. Everyone who participated in the execution of Lisa Montgomery should feel shame," she said in a statement. "The government stopped at nothing in its zeal to kill this damaged and delusional woman. Lisa Montgomery’s execution was far from justice."

DEATH ROW INMATES' LAST WORDS

Lisa Montgomery, 52, was pronounced dead at 1:31 a.m. after receiving a lethal injection. (Attorneys for Lisa Montgomery via AP, File)

Advocates against the death penalty also accused Trump of pushing for executions before the election in a cynical effort to gain votes. 

Henry told the Associated Press she didn't believe Montgomery had "any rational comprehension of what’s going on at all" before her execution. 

She added that Montgomery had had all of her coping mechanisms, like her ability to do needlepoint, taken from her when she arrived at the federal facility late Monday night to prevent suicide. 

Henry said she was being kept in a cell in the execution-chamber building itself because there was no place for female inmates. 

Montgomery was granted a stay of execution Tuesday by an appeals court shortly after another appeals court lifted an Indiana judge’s ruling that found she was likely mentally ill and couldn’t comprehend she would be put to death. But both appeals were lifted, allowing the execution to go forward. 

Montgomery killed 23-year-old Bobbie Jo Stinnett in the northwest Missouri town of Skidmore in 2004. She used a rope to strangle Stinnett, who was eight months pregnant and then cut the baby girl from the womb with a kitchen knife. Montgomery took the child with her and attempted to pass the girl off as her own. She had driven around 170 miles from her home in Kansas. 

She arrived at Stinnett's house under the guise of adopting a puppy -- the two had met at dog shows -- then kidnapped the premature baby after telling her husband she had been pregnant. She later told him she had gone to a birthing center to have the baby that day.  

Montgomery’s legal team says she suffered "sexual torture," including gang rapes, as a child, permanently scarring her emotionally and exacerbating mental-health issues that ran in her family.

During her trial, prosecutors made accusations that Montgomery was faking her mental illness because the murder was premeditated but Henry said she had seen brain scans that supported her diagnosis.  

"You can’t fake brain scans that show the brain damage," she said.

Henry said the issue at the core of the legal arguments is not whether she knew the killing was wrong in 2004 but whether she fully grasps why she is slated to be executed now.

The government admitted her mental illness but said Montgomery should be able to understand she was being executed for committing murder. 

In his ruling on a stay, U.S. District Judge James Patrick Hanlon in Terre Haute cited defense experts who alleged Montgomery suffered from depression, borderline personality disorder and post-traumatic stress disorder.

Montgomery, the judge wrote, also suffered around the time of the killing from an extremely rare condition called pseudocyesis in which a woman’s false belief she is pregnant triggers hormonal and physical changes as if she were actually pregnant.

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Montgomery also experienced delusions and hallucinations, believing God spoke with her through connect-the-dot puzzles, the judge said, citing defense experts.

"The record before the Court contains ample evidence that Ms. Montgomery’s current mental state is so divorced from reality that she cannot rationally understand the government’s rationale for her execution," the judge’ said.

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Prosecutors said Stinnett regained consciousness during her attack and tried to defend herself. Montgomery was arrested the next day after showing off the baby, Victoria Jo, who is now 16 years old and hasn’t spoken publicly about the crime.

The motive, according to prosecutors, was that Montgomery’s ex-husband knew she had undergone a tubal ligation that made her sterile and planned to reveal she was lying about being pregnant in an effort to get custody of two of their four children. Needing a baby before a fast-approaching court date, Montgomery turned her focus on Stinnett. 

The other two men scheduled to be executed - Corey Johnson and Dustin Higgs - had theirs stayed by a federal judge in the District of Columbia Tuesday after they both tested positive for the coronavirus last month. 

The executions were scheduled for later in the week. 

Johnson was convicted of killing seven people related to his drug trafficking in Virginia, and Higgs ordered the murders of three women in Maryland.

The last woman executed by the federal government was Bonnie Brown Heady on Dec. 18, 1953, for the kidnapping and murder of a 6-year-old boy in Missouri.

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The last woman executed by a state was Kelly Gissendaner, 47, on Sept. 30, 2015, in Georgia. She was convicted of murder in the 1997 slaying of her husband after she conspired with her lover, who stabbed Douglas Gissendaner to death.

The Associated Press contributed to this report.