Marlise Munoz: Can a fetus survive after mother becomes brain-dead?

At the center of a dispute over whether a Texas hospital can keep a brain-dead woman on life support is a 21-week-old fetus.

Marlise Munoz was 14 weeks pregnant when her husband, Erick, discovered her lying unconscious on their kitchen floor in the middle of the night. The 33-year-old woman was taken to John Peter Smith Hospital in Fort Worth, “where doctors informed Erick that Marlise had lost all activity in her brain stem, and was for all purposes brain dead,” according to a civil court petition filed Tuesday in Tarrant County.

That was on Nov. 26. In the seven weeks since, the hospital has kept Munoz on life support – against the wishes of her family – in the hope that she may still deliver a healthy baby. The hospital says it is compelled to do so by the Texas Advance Directives Act, which says in part: “A person may not withdraw or withhold life-sustaining treatment under this subchapter from a pregnant patient.”

Erick Munoz, Marlise’s parents and several medical and legal experts agree that the state law doesn’t apply on the grounds that Marlise is not a “patient” because she is dead. As the tragic case of 13-year-old Oakland girl Jahi McMath brought to light, brain death – defined as the “irreversible cessation of all functions of the entire brain, including the brain stem” – qualifies as a legal death.

Erick Munoz has filed suit to force the hospital to remove Marlise from the machines sustaining her body. But if her body is kept going until her baby can be delivered, what are the odds of success? That’s impossible to know, but there is a study that offers some clues.

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Researchers from Heidelberg University in Germany scoured the medical literature for cases of pregnant women who were kept on life support after being declared brain-dead. They were able to find details on 19 such cases that were reported from 1982 to 2010.

Twelve of those fetuses were delivered by caesarean section and survived for some period of time after birth. One of the babies, born prematurely after just 25 weeks of gestation, died of an infection at the age of 30 days. Six of the others were developing normally as of the time that case reports about them were written (at ages ranging from 3 to 24 months), though a few of them had suffered from infant respiratory distress syndrome. The condition of the other five babies was unknown.

Another five of the fetuses died in utero, and a sixth died at 19 weeks’ gestation after a miscarriage.

The last fetus was delivered by caesarean section at 32 weeks’ gestation, but whether it survived birth was not known.

Among these 19 cases, there is one fetus that was 14 weeks old when its mother was declared brain-dead – the same age as the fetus in the Munoz case. That 1994 case involved a woman who was killed in a traffic accident in Germany. It’s not clear how long the woman remained on life support, but the fetus died in utero.

Two other cases involved a fetus that was 13 weeks old. One of them, in Ireland in 2004, died in utero eight days after its mother suffered a blood clot in the brain. The other, whose mother was in an accident in Germany in 1993, survived for 38 days before dying as a result of miscarriage.

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There were also two cases involving fetuses that were 15 weeks old when their mothers died. One of the fetuses died in utero 49 days after its mother suffered catastrophic bleeding in the brain in Italy in 1992. The other remained in utero for 107 days – more than 15 weeks – after its mother suffered a traumatic brain injury in the U.S. in 1989. That baby boy was delivered by C-section at 32 weeks; he weighed 3.4 pounds, had Apgar scores of 6 and 9 (scores lower than 7 indicate a newborn needs medical attention, according to the National Institutes of Health), and was developing normally 11 months after his birth.

The fetus in the Munoz case has been developing in utero with a brain-dead mother for 49 days so far. Six of the cases described in the study involved a fetus that remained in utero with a brain-dead mother longer than that. In five cases, the babies were delivered by C-section; one of them died after 30 days and the other four survived. No information was available on the sixth.

All of these cases involved a fetus that was older the Munoz fetus at the time of its mother’s injury.

“The important question is from which gestational age onward should the pregnancy be supported?” the study authors wrote. “At present, it seems that there is no clear lower limit to efforts to support the brain-dead mother and her fetus.”

But the authors of the study cautioned that their data were incomplete and could not be used to determine the likelihood that a fetus could survive after its mother became brain-dead. “The percentage of successful cases cannot be determined, because there are no reports describing failure of intensive maternal support from all medical centers,” they wrote.

The study was published in 2010 in the journal BMC Medicine.

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