A group of doctors called on an appeals court to consider the ability of a fetus to feel pain in examining an Arizona law preventing abortions after 20 weeks of pregnancy.

“Hormonal, behavioral and physiologic evidence supports the legislature’s conclusion that a fetus at 20 weeks gestation feels pain,” read the amicus brief, filed with the Ninth U.S. Circuit Court of Appeals. 

It argued that the state has an established interest in eliminating or reducing “activities that provoke pain.”

The brief was filed on Oct. 10 on behalf of Doctors on Fetal Pain, a physician and medical researcher association that seeks to raise awareness about evidence showing the ability of unborn children to experience pain.

The case, Isaacson v. Horne, challenges an Arizona law to ban abortions after 20 weeks of pregnancy except in cases of medical emergency. In forming the law, state legislators took into account scientific and medical evidence indicating that unborn children can feel pain at this point in development.

While the law’s opponents argue that fetal ability to feel pain should not be legally relevant, the brief maintained that “the issue of at what point the unborn experience pain is an important one that should inform best medical practice.”

A district court ruled in favor of the legislation in July. Shortly afterwards, the appeals court temporarily blocked the law’s implementation while it considered the case.

The amicus brief urged the circuit court to affirm the lower court’s ruling, which held that the law is a “constitutionally permissible regulation of abortion.”

“In choosing to put a limit on abortions past 20 weeks gestational age, the Arizona Legislature cited the substantial and well-documented evidence that an unborn child has the capacity to feel pain during an abortion by at least 20 weeks gestational age,” the district court had said.

This evidence included the biological development of a fetus, such as the fact that “by 7 weeks gestational age, pain sensors develop in the face of the unborn child and, by 20 weeks, sensory receptors develop all over the child's body, and the children have a full complement of pain receptors.”

In addition, the lower court had observed, “When provoked by painful stimuli, such as a needle, the child reacts, as measured by increases in the child's stress hormones, heart rate and blood pressure.” These responses decreased when the child was given anesthesia, which doctors often do during fetal surgery.

For these reasons, the district court concluded that the state had shown a legitimate interest in limiting abortions past 20 weeks.

Doctors on Fetal Pain agreed with this reasoning, explaining that fetal pain is a relevant consideration in forming state laws on abortion.

Although courts have reached different opinions on the “existence and extent of fetal pain during abortion,” they recognize that “fetal pain is legally relevant to the regulation of abortion,” the brief noted.

It pointed to a 2007 court ruling stating that lawmakers have “wide discretion to pass legislation in areas where there is medical and scientific uncertainty.”

“One of the most basic and widely accepted principles of political governance is that that the state is justified in promulgating laws to protect individuals from harm by others,” the document said. Recognized in both domestic and international law, the power to protect against physical harm encompasses “all living creatures,” as seen in long-standing laws against animal cruelty.

Furthermore, courts have recognized that abortion involves not only a woman, but also the “whole, separate, unique, living human being” that she carries, the brief observed.

This is true regardless of whether the unborn child is at a point of viability, it explained, pointing to a 2007 Supreme Court ruling that “a fetus is a living organism while within the womb, whether or not it is viable outside the womb.”

For these reasons, the Arizona Legislature’s considerations on fetal pain “should be given weight” in reviewing the case, the brief argued: “The court should affirm the decision of the district court: that Arizona has a constitutionally recognizable interest in limiting the infliction of pain on the unborn.”