WSJ, March 15: Adeza News

March 15, 2005

AN UNDERUSED SCREENING TEST is available to pregnant women that can help rule out the largest cause of death and disorders among newborns.

Unlike amniocentesis or cystic-fibrosis testing, this exam is designed to judge not the health of the baby but the health of the pregnancy itself. The so-called fetal fibronectin test, or fFN, measures the risk of preterm delivery, defined as birth that occurs at less than 37 weeks' gestation. About 400,000 babies each year are born prematurely, putting them at risk for death and often serious health problems.

The benefits of the test are limited because of its high rate of false positives. In studies of women with symptoms of preterm labor, about 40% of those with a positive fFN reading -- indicating a risk for early delivery -- carried their babies to term anyway. Such false positives can push a woman's anxiety level higher than if she hadn't taken the test, and could lead to unnecessary medical treatment.

But the vast majority of fFN tests have come back negative, and here is where their value resides. In women who have symptoms of preterm labor -- such as contractions or unusual discharge -- a negative score signals a better-than-90% chance that delivery will not occur in the next two weeks. That may not seem like much, but it can spare a woman anxiety as well as unneeded medical treatment during that time. And some doctors repeat the test to continually update a woman's risk. In a woman without preterm-delivery symptoms, the all-clear zone lasts four weeks.

Nicole Baker, at high risk for preterm labor because of prior abdominal surgery and because she was carrying twins, was able to keep working at a Manhattan law firm through the majority of her pregnancy last year only because of three negative fFN findings. "The peace of mind that test gave me was incredible," says Ms. Baker, who delivered healthy twins in the 36th week of her pregnancy.

About two in 10 pregnant mothers either have risk factors or symptoms of preterm labor. Risk factors include multiple fetuses and a previous preterm delivery. Yet only about one in eight babies is born prematurely, often from a mother who had neither symptoms nor risk factors.

The standard measures for determining which women actually are experiencing preterm labor -- contraction frequency and a digital exam -- aren't that accurate. Using those measures, "we overdiagnose premature labor probably 30-40% of the time," says Jay Iams, professor of maternal fetal medicine at Ohio State University.

Thus, thousands of women every year are placed unnecessarily on bed rest and perhaps on medications to slow delivery and speed fetal development. Some are hospitalized, racking up huge bills.

Since its introduction in 1999, the fFN test has helped diminish that problem, as has a more expensive and difficult-to-administer exam called the cervical ultrasound. Dozens of peer-reviewed research papers, in publications such as the New England Journal of Medicine and the American Journal of Obstetrics and Gynecology, support their value as negative indicators of preterm labor.

But many leading obstetricians, including Dr. Iams, say that both tests are underused, in part because they're relatively new. The fFN test was administered about 300,000 times last year on far fewer women than that, since many underwent it repeatedly. And the cervical exam is believed to have been administered more rarely still. Meanwhile, the number of U.S. women with preterm-labor symptoms or risk factors each year is estimated at about 800,000.

These obstetricians say that high-risk or symptomatic women should ask for the fFN test, which a nurse can administer and which produces results in as little as an hour. The fFN exam involves obtaining a swab from the cervix to test for the presence of fetal fibronectin, a protein that helps hold the baby in place but that starts to leak out when labor is near. It is effective after the 22nd week, and in such women the $240 cost is generally covered by insurance. In symptomatic women, the test is also recommended by the American College of Obstetricians and Gynecologists.

After Angela Pechacek's first pregnancy ended too early for the baby to survive, she began having contractions during the 25th week of her second pregnancy. This would have meant weeks, perhaps months, in the hospital if not for two negative fFN tests. Despite continuing contractions, "those tests gave me the confidence to go home," she says. Her second baby was born full-term and healthy.

The fFN test is generally not recommended for women at average risk for preterm labor, because of the high false-positive rate. The test's manufacturer, Adeza Biomedical Corp., is expanding its marketing efforts, promoting the test at obstetricians' offices as well as to pregnant women themselves. "Any woman who wants our test should request it from her doctor," says Emory V. Anderson, president and chief executive officer. He says the test offers value not only to at-risk women but also to first-time mothers and others. The fFN test accounts for about 95% of sales at publicly traded Adeza Biomedical, whose 2004 sales were $33.6 million.

But that position diverges from that of the medical community, including Charles J. Lockwood, chairman of obstetrics and gynecology at Yale University School of Medicine and a consultant to Adeza.

A big supporter of the test among at-risk or symptomatic women, Dr. Lockwood says: "If you're just a healthy patient, and everything's going great, you ought not to ask for this test."