Despite the test's less-than-perfect record, Bourque saw no reason for concern. Using a formula that combines the levels of AFP, estriol, and hCG with mathematical values for Tierney's age, weight, race, and family history, he concluded with great confidence that the odds of Tierney having a child with Down syndrome or a neural tube defect were extremely low.
The chance of Down syndrome was particularly small. Stamped across the bottom of the one-page report tucked into Tierney's medical file were two words: SCREEN NEGATIVE. It was only below that, in tiny print, that a disclaimer read: "It should be noted that normal test results can never guarantee the birth of a normal baby, and that 2 to 3 percent of newborns have some type of physical and mental defect, many of which are undetectable through any known prenatal diagnostic technique." Tierney didn't see the disclaimer, but she wouldn't have worried about it, anyway. Instead, she and Greg focused on the big picture: SCREEN NEGATIVE. That result, combined with the first ultrasound performed on Tierney in April, meant Bourque had no reason to order more costly, complicated — and more definitive — diagnostic tests. A "Prenatal Diagnosis Screening" form Tierney had filled out also bolstered Bourque's confidence. Of twenty-two questions about her and Greg's personal and family medical histories — everything from hereditary chromosomal abnormalities and hemophilia to muscular dystrophy and sexually transmitted diseases — Tierney had answered "no" to every question but one. She wrote that she had an uncle with a birth defect, but she didn't elaborate. It didn't seem necessary, and Bourque didn't consider it significant enough to ask about it.
Tierney was a smart young woman with an impressive resume, on course for a successful future. She had an undergraduate degree from the University of Pennsylvania, a master's in business administration from the Darden Graduate School of Business Administration at the University of Virginia, and a Ph.D. in education from UVA as well. In 1994, she had been hired to manage education programs for United Technologies Corporation, a huge Hartford-based aerospace and industrial company.
Tierney was five-foot-six, slim and pretty, with large brown eyes, silky, shoulder-length brown hair, and a scrubbed peach complexion. She had her mother's voice, a teacher's voice, sweet in the lower registers and prone to cracking when she got excited and it soared by an octave. She was a hard worker — an overachiever since early childhood, her mother had always said — focused and organized, with a storehouse of energy that allowed her to work or play for long hours with little sleep. She had ready access to her emotions but usually displayed a professional exterior, steely at times. She had a wary side, and she would furrow her brow and narrow her eyes as she worked to understand a point and gain insight into the person making it. When she felt comfortable, she shared an effervescent laugh and a mischievous sense of fun. She had a gleaming white smile, and she was proud of it.