Despite the petition, pro-life Members of Parliament aknowledged there was little chance of a ministerial intervention.
Jacob Rees-Mogg, MP for North-East Somerset, told CNA that "This is deeply troubling but there is no Parliamentary route to challenging this decision."
Doctors who cared for the woman argued that due to her mental capacities, either natural labor or cesarean section delivery could damage her mental health. Her mother, described as a former midwife, along with a social worker who helps care for the woman, both disagree and do not wish to terminate the pregnancy.
The petition also drew attention Lieven's "past advocacy for [the] abortion provider BPAS and her claim that Northern Ireland's abortion law is akin to torture."
In Northern Ireland, abortion is only permitted in instances when the mental or physical health of the mother is at risk. BPAS, the British Pregnancy Advisory Service, is the largest abortion provider in Britain.
Lieven has said that she is "acutely conscious" that ordering an abortion for a woman who did not want one was an "intense intrusion" by the state.
"I have to operate in [her] best interests, not on society's views of termination," Lieven explained in her decision. Lieven also suggested it would be more traumatic if the woman were to lose custody of her child, who would be a "real baby" after birth.
The woman's mother offered to care for her grandchild, but Lieven dismissed this idea as impractical due to the pregnant woman's mood disorder and developmental delays.
Two Catholic bishops from the United Kingdom also spoke out against the decision.
"Forcing a woman to have an abortion against her will, and that of her close family, infringes upon her human rights, not to mention the right of her unborn child to life in a family that has committed to caring for the child," said Bishop John Sherrington, an auxilary bishop of the Archdiocese of Westminster.
Sherrington serves as the designated spokesman on life issues for the Catholic Bishops' Conference of England and Wales.
(Story continues below)
Subscribe to our daily newsletter
"In a free society like ours there is a delicate balance between the rights of the individual and the powers of the state," he added. "This is a sad and distressing decision for the whole family whom we keep in our prayers. This case, for which all information is not available, raises serious questions about the meaning of 'best interests' when a patient lacks mental capacity and is subject to the court's decision against her will."
Officials at the Archdiocese of Westminster told CNA that Cardinal Vincent Nichols would not be making a statement of his own.
Bishop John Keenan of the Diocese of Paisley, in Scotland, urged people to sign the petition in a video posted to Twitter by March4LifeUK. Keenan said that the decision "introduces a dangerous new development in the overreach of the power of the state over its citizens," and "has to be changed."
The decision is troubling, Keenan said, "not just in the interests of this woman and her child, but in the interests of everyone who believes in choice in this country, in the interests of everyone who believes in the prerogatives and the rights of citizens over the state."
Scotland has both a separate court system from England and Wales, and the Catholic hierarchy of Scotland has its own bishops' conference.
Police are investigating the circumstances of how the woman became pregnant.