In an unusual case that raises complex ethical issues, a 43-year-oldwoman is having a baby in hopes that the newborn can become a bone marrow donor for her teen-age daughter, who is dying of leukemia.
"I never thought I'd be pregnant at my age, but when you're faced with the possibility that your child is going to die, you desperately seek, and whatever you need to do, you do it," said Mary Ayala, who is due in mid-April.
Although family members are the best sources for transplants, none of the Ayalas proved compatible when tested. A search by the National Marrow Donor Program of unrelated donors - with only a one-in-20,000 chance of a match - also came up empty.
Doctors said the bone marrow can be obtained with little risk to an infant who is at least 6 months old. And doctors say that the Ayalas' teen-age daughter, Anissa, is likely to still be alive then. The chances that the two siblings' tissues will be exactly compatible are about one in four.
Medical ethicists interviewed Thursday said it is extremely rare for a baby to be conceived specifically to serve as a bone marrow donor for an ailing family member, and the Ayala case raises a number of ethical issues.
Unlike adults, children are unable to give informed consent for medical procedures such as marrow donation. Such legal consent is usually given on their behalf by a parent or guardian.
"What they're doing ethically is very troubling, but on the other hand, I can sympathize with their desire to do everything possible to save their daughter's life," said Alexander Capron, professor of law and medicine at the University of Southern California
in Los Angeles.
"How much potential pain and risk can one parent demand of one sibling for the benefit of another sibling?" asked Jake Priester, a research fellow at the Center for Biomedical Ethics at the University of Minnesota.
The Ayalas defend their choice and are dismayed that anyone would even question their motives.
"If it's not a match, we will love our baby just the same," Mary Ayala said softly. The new baby, she said, "would give Anissa lots of enthusiasm, it would make her fight to stay alive to see her grow up."
Abe and Mary Ayala decided to go ahead with the pregnancy even though Anissa's doctor, a pediatric oncologist, advised Mary not to become pregnant just for Anissa's sake.
"I thought it was a peculiar reason to have a baby," the oncologist, Dr. Patricia Konrad, said. "It made me uncomfortable; it didn't sit well, if that was the only reason, to have a child to help another child."
Konrad nonetheless plans to perform the transplant if the infant girl, whose sex was revealed through amniocentesis, proves to have compatible tissue.
If the baby's tissue matches, Anissa's doctor will begin the long and painful process of preparing her for the transplant by destroying her existing marrow through applications of radiation and chemotherapy.
The harvesting of the marrow, as the medical procedure is known, is done under general anesthetic, during which a thick needle is inserted into the marrow cavity of the donor's hip bone. Konrad said a healthy donor can regenerate the extracted marrow within a week.
The marrow is prepared and then injected into a vein of the recipient, similar to a blood transfusion.
In the meantime, the Ayalas are waiting out the last two months of
"We face it every day, that maybe today Anissa gets sick," Mary Ayala said. "But you just can't dwell on it. We're just waiting and hoping that our miracle baby will be the miracle baby that Anissa needs."