In the late 1960s, medical researchers developed a way to find genetic defects in a fetus as young as 15 weeks, early enough to terminate a pregnancy with an abnormal fetus. Despite the need to have a long needle inserted into the uterus, many expectant mothers gratefully embraced amniocentesis, the now familiar genetic test. “It is truly a miracle,” a new mom told The New York Times in 1971. The woman’s three sisters had Down syndrome, and she had been terrified of passing on the disorder but got a null result. “I never thought I could have normal, healthy children.”
Another miracle is just around the corner: Researchers in Hong Kong and California are developing a technique that could read the entire contents of a fetal genome as early as 9 weeks into pregnancy, using very little blood from the mother. The test could reveal severe genetic disease, as well as a child’s eye color, and someday perhaps even height, intelligence, or athletic ability. It would be safe, affordable, and fast, but ethically challenging. “It’s very controversial,” says Arthur Beaudet, a pediatrician and genetic disease expert at Baylor College of Medicine. “Some families wouldn’t consider termination under any circumstances. But when faced with solid evidence of disabilities, many people give more thought to termination than they ever expected.”