Viability — the period when a fetus can survive outside the mother’s womb — has become a key factor in efforts to restrict abortion, with pro-life advocates and politicos citing medical advancements that have allowed premature babies to survive after shorter pregnancies.
The issue will likely play a significant role when the Supreme Court hears arguments in its upcoming term in a lawsuit opposing Mississippi’s ban on abortions after 15 weeks of pregnancy. The case directly challenges the high court‘s precedent in the 1973 Roe v. Wade decision, which established a right to abortion before the third trimester.
Medical technology has changed since 1973, when viability was determined to occur “at about seven months (28 weeks) but may occur earlier, even at 24 weeks,” according to the Supreme Court‘s ruling in Roe.
The world’s earliest successful premature birth occurred in June 2020, when Richard Hutchinson was born at 21 weeks and two days, weighing less than a pound. He celebrated his first birthday this summer, according to The Washington Post.
In Mississippi’s legal battle, the state moved to present evidence about viability and medical advances. A filing tells the justices that a lower court did not allow such evidence to be presented in its defense of the state’s 15-week abortion ban.
Medical and legal authorities now say viability is reached around the 24th week of pregnancy, with rare births as early as 21 weeks.
“It might be better for pregnant people to have a clear date beyond which abortion is prohibited,” said Lois Shepherd, a biomedical ethics and law professor at the University of Virginia who is not involved in the Mississippi case.
However, Ms. Shepherd added that exceptions should be made for a woman’s health.
Kate Connors, a spokesperson with the American College of Obstetricians and Gynecologists, said when it comes to viability, “there’s just simply no cut-and-dry answer because pregnancies are different.”
According to the OB-GYN group’s guidance, studies over the past three decades have shown a progressive increase in survival for infants born at 22 weeks through 25 weeks.
However, the group noted that studies also show babies born that early typically face moderate to severe impairments such as loss of sight or hearing and cerebral palsy.
Dr. Nisha Verma, a fellow at the American College of Obstetricians and Gynecologists and a family planning and abortion expert, said defining viability, even broadly, is impossible because each pregnancy progresses differently and some pregnancies face more challenges than others.
Although infants born at 23 weeks do survive nowadays, she said, they usually endure long-term and extensive medical intervention because of severe complications.
“Although improvements in technology and medical care have increased the odds of survival earlier in pregnancy, it is impossible for clinicians to know with certainty whether an infant without specific medical diagnoses who is born at this point in gestation will survive,” Dr. Verma said.
Other authorities agree and note that the chance of survival for some infants can depend on the facility where they are born.
“Courts don’t often set a fixed limit precisely because viability changes as technology improves and may vary from hospital to hospital. There has been a lot of criticism of the viability line for this reason, and bioethicists have questioned whether it maps well onto intuitions about when life has value,” said Mary Ziegler, a law professor at Florida State University.
Mississippi is bringing its case before the Supreme Court after enacting a law in 2018 prohibiting abortion at 15 weeks. Abortion providers challenged the law. Lower courts issued an injunction halting enforcement.
The Supreme Court held in Roe v. Wade that women have a right to an abortion up until viability and affirmed that ruling in Planned Parenthood v. Casey in 1992.
In Roe, the court said a state has an interest in regulating abortion in the second trimester in instances for the life of the mother. Examples included certain requirements for the physician and provider performing the procedure. Abortion can be prohibited in the third trimester, after viability, the court ruled.
Mississippi contends that the viability standard set in 1973 is unclear and obstructs a state’s interest to protect the life of the woman and the unborn.
The state says it has an interest in banning abortions after 15 weeks to protect women’s health. It cites increasing risks of abortion to women as pregnancies continue.
State officials wanted to provide evidence of medical advancements, but the lower court did not allow the state to introduce data showing that a baby develops stimuli and feels pain earlier than was believed in 1973.
“Imposing an inflexible viability standard eviscerates the states’ ability to account for ‘advances in medical and scientific technology [that] have greatly expanded our knowledge of prenatal life,’” Mississippi says in its filing.
Whether a state can ban abortion before a fetus is viable has been at the center of debate over laws enacted in conservative states, not just Mississippi.
Texas has banned abortion after a fetal heartbeat is detected, usually around six to eight weeks of pregnancy.
Under the Texas law, the state does not enforce the ban. Rather, individuals can sue abortion providers in civil court if they are known to have performed an abortion after the detection of a fetal heartbeat.
The Supreme Court did not block the Texas law from taking effect this month. Abortion providers and the Justice Department are challenging its constitutionality in lower courts.