Routine Electronic Monitoring Of Fetuses Is Challenged in Study

By WARREN E. LEARY

New York Times, A11, Oct. 25 N

Electronic fetal monitoring during labor and delivery, used with a majority of births in this country, offers little significant benefit to justify its routine use, according to researchers reviewing the practice.

Researchers at the Federal Centers for Disease Control and Prevention in Atlanta said a review of the most significant controlled studies of the effectiveness and safety of electronic fetal monitoring indicated that routine use of the procedure had no measurable effect on death or illness of infants or mothers.

But they said electronic monitoring was associated with a higher rate of Cesarean deliveries, which increases surgical risks to mothers.

In view of the findings, they said, a review of the widespread practice of electronically monitoring fetal heart rate and contractions during labor is warranted. Electronic monitoring, introduced in the late 1960's, is now used during labor in three out of four pregnancies in the nation, they said, and studies are needed to determine who benefits from this kind of surveillance and who does not.

The researchers, led by Dr. Stephen B. Thacker of the centers' Epidemiology Program Office, reviewed 12 controlled trials of fetal monitoring published from 1966 to 1994. These studies included 58,855 women and 59,324 infants in both low- and high-risk pregnancies from 10 centers in the United States, Europe, Australia and Africa.

Fetal heart rate is a good indicator of stress on the fetus in labor and delivery, experts say. Normal heart rate suggests that the fetus is extracting enough oxygen from the woman's bloodstream through the placenta and umbilical cord. But variations in the heart rate can indicate decreased oxygen in the blood and tissues of the fetus, which can lead to potential damage to the brain, central nervous system and organs. In severe cases, this can result in death.

Most electronic monitoring is done with an ultrasound device attached to a belt put around the woman's abdomen. A computerized component of the device counts and interprets the signals to assess fetal heart rate and the contractions of labor. Electronic fetal monitoring has been controversial for years, with some women's health groups charging that it was accepted as standard practice before its effectiveness was proven and that it was an unnecessary interference in childbirth, particularly in low-risk pregnancies. Some doctors also say the devices result in unnecessary Cesarean sections because they can erroneously indicate that a fetus is in trouble.

The new study, published in the October issue of the journal Obstetrics and Gynecology, found that electronic monitoring was not measurably better in spotting distress and indicating that intervention was necessary than the traditional practice of intermittent auscultation. With this method, a nurse or midwife closely monitors fetal heart rate with a stethoscope. If a problem is detected, the nurse can reposition the woman to relieve pressure that may be restricting the fetus's oxygen or give extra oxygen to the mother to increase levels in her blood stream.

The American College of Obstetricians and Gynecologists, in guidelines issued in 1988 and revised this summer, recommends monitoring all labor either electronically or with auscultation, but leaves the decision to the woman and her doctor. But a Federal health study group in the United States and a similar body in Canada recommend that electronic monitoring be reserved for high-risk pregnancies, such as cases when a woman enters labor prematurely, has a history of problem deliveries or has a complicating disease like diabetes or sickle cell anemia.

Dr. Frank H. Boehm, a professor of obstetrics and gynecology at Vanderbilt University and a proponent of electronic monitoring, said the method had improved since its introduction and provided some benefits not mentioned in the latest study. The latest generation of monitoring equipment is more reliable and accurate than earlier models, he said, and as doctors and nurses gain more experience with electronic monitoring, they more accurately interpret the information it provides.

The new study, whose other authors were Dr. Donna F. Stroup and Dr. Herbert B. Peterson, said the only significant benefit of electronic monitoring found was a reduction in neonatal seizures sometimes seen in the first month after birth. Such seizures are associated with about one-half of 1 percent of all births, Dr. Thacker said in an interview.

But he said the only two studies done to date on the long-term effects of these seizures on infants indicated that they were minimal and rarely resulted in major adverse conditions, like cerebral palsy.