A Colorado woman has been sentenced to a total of 100 years in prison for attempted murder after cutting a seven-month-old foetus from the womb of an expectant mother.

Dynel Lane was found guilty by a jury for trying to kill Michelle Wilkins in March 2015 in the Denver suburb of Longmont and was also convicted of the unlawful termination of a pregnancy. The baby, later named Aurora, did not survive the attack.

Judge Maria Berkenkotter said the sentence was justified by the brutality of the attack, which she described as performing a caesarean with a kitchen knife.

Prosecutors had asked for the maximum sentence of 188 years.

Lane faked a pregnancy for months before luring Ms Wilkins, 28, to her apartment by creating a Craigslist ad for maternity clothes.

Lane hit Ms Wilkins over the head with a lava lamp and stabbed her in the neck with the broken glass. She then cut Ms Wilkin’s abdomen, removed the unborn baby and left the victim for dead.

When the judge asked Lane if she wanted to speak, she declined.

In 2002, Lane’s 19-month-old son drowned in what investigators decided was an accident. Relatives who spoke on Lane’s behalf before the sentencing said her remorse over losing her son may have led to the attack on Ms Wilkins.

Ms Wilkins spoke to her attacker in court in Friday, in front of a photograph of her dead baby on an easel next to the witness stand.

“It is clear that you need healing and I hope that you get it,” Ms Wilkins said to Lane.

Ms Wilkins asked Judge Berkenkotter to impose the harshest possible sentence on Lane. She said after the sentencing that she saw the hearing as a day in court for her daughter.

“Judge Berkenkotter was clearly listening to everything that we were saying,” Ms Wilkins told reporters.

Prosecutors said they could not charge Lane with murder of the baby because there was no evidence the fetus lived outside the womb.

Colorado Republicans introduced legislation that would have allowed such a murder charge, but it was rejected by Democrat politicians.

To date 38 US states have made the killing of a foetus a homicide despite objections from abortion-rights supporters.