Susan, who was 22 weeks pregnant, eased into one of the hard-back chairs, smoothed the smock over her belly and instinctively reached for Jason's hand.

"This is so hard," she said, sighing.

Four days before, Susan and Jason had arrived at Vanderbilt University from Holly Springs, N.C. Now they had just 24 hours left to make a decision that would change their lives and the future of their unborn child.

Four weeks earlier, Susan and Jason learned that the baby they so eagerly awaited -- a girl, her name would be Anna -- had spina bifida.

Since then, they had taken a crash course in a difficult subject, dutifully gathering all the reports, all the numbers, all the odds that had somehow hit: One newborn in 1,000 is afflicted with the paralyzing defect. It meant Anna might never walk; that she would probably need brain surgery, perhaps several times; that she would be susceptible to constant urinary infections and kidney disease.

Doctors explained that many parents in the Williamsons' position decide to end the pregnancy. Susan and Jason dismissed that idea right away; abortion was simply not an option.

But was doing nothing the only alternative?

That was the question that had led them here -- to Vanderbilt, to this surgeon's office. They were exploring a third path, and it was a medical experiment.

Two of the university's doctors proposed operating on Anna in the womb, cutting open Susan's uterus and repairing Anna's defect in the tender months before birth. The operation, the doctors said, would give Anna a chance for a more normal life. But the doctors wanted to operate now, during Susan's 22nd week of pregnancy, because the earlier they went in, the better the results. So the Williamsons needed to decide by the next day.

The procedure was risky. Only 89 other women had dared to undergo the Vanderbilt procedure. One baby had died. Others had been born prematurely, some dangerously so. One mother's uterus broke open during labor.

Susan and Jason recited the results like scientists at a symposium. They folded the reports and pamphlets -- a small library of data -- into the black vinyl backpack Jason carried with him everywhere. He set it on the floor of the surgeon's office, plopped himself into the chair and reached for Susan's hand.

Twenty-four hours left to decide. One day, a lifetime.

"All we can do is go with our feelings," Jason said, "and trust that it's the right thing."

The first of four

Susan and Jason were both 27, and for as long as they had known each other, they had wanted four children. They decided to start trying for the first of those children last year. Finally, on the morning of Jan. 8, 2000, they passed the results of a home pregnancy test back and forth, double-checking against wishful thinking that it really showed a plus sign.

Sure enough, they were pregnant.

Days before that morning -- before they had any reason to suspect Susan was pregnant -- the cells that formed Anna's body had been busy dividing, and dividing again. Somewhere around the 21st day after conception, when Anna was no larger than a grain of rice, a virtual explosion of cells created her spinal column and brain.

As the cells formed, they were already programmed to become bone, nerve, muscle, skin -- and they began moving into their assigned places, starting at the midpoint in her back and working in both directions to form the neural tube.

Next page >