Updating a Standard: Fetal Monitoring

Take a moment to read this article about External Fetal Monitoring from yesterday’s New York Times. It has become a real issue and a routine practice in so many hospitals.

July 7, 2009
New York Times
By JANE E. BRODY

Electronic fetal monitoring during labor and delivery was introduced into obstetrical practice in the early 1970s in hopes that it would reduce the risk of cerebral palsy and death resulting from inadequate oxygen to the fetal brain.

The monitors continually measure the fetal heart rate and produce tracings on a screen and paper that can alert a doctor to a baby who is doing poorly under the stress of labor. It is up to the doctor to try to alleviate the problem and, if those measures do not help, to decide whether to deliver the baby vaginally with forceps or surgically by Caesarean.

Today, more than 85 percent of the four million babies born alive in this country each year are assessed by electronic fetal monitoring, amid continuing controversy over whether it does more harm than good. New guidelines on fetal monitoring, published this month, aim to bring more consistency to how doctors interpret the results and act on them.

“Honestly, the technology got rolled out before we knew if it worked or not,” Dr. George A. Macones, an obstetrician at Washington University in St. Louis, said in an interview.

Continuous monitoring became a standard obstetrical procedure before studies could show if the benefits outweighed the risks, and without clear-cut guidelines on how doctors should interpret the findings.

But experts report that the use of fetal monitoring has produced both negative and positive results, including these:

¶Electronic monitoring has led to a significant increase in both Caesarean deliveries and forceps vaginal deliveries.

¶Monitoring results are widely used by lawyers to bolster malpractice cases of spurious merit, which has led to soaring costs for malpractice insurance and, in turn, prompted many obstetricians to stop delivering babies.

¶Electronic monitoring has not reduced the risk of either cerebral palsy or fetal deaths.

Revised Guidelines

Last year a workshop held by the Eunice Kennedy Shriver National Institute of Child Health and Human Development produced new recommendations that have now been incorporated into revised practice guidelines by the American College of Obstetricians and Gynecologists and published in the July issue of the journal Obstetrics & Gynecology. Dr. Macones supervised the development of the new guidelines.

The college hopes the revised guidelines will reduce misinterpretations and inconsistencies in the understanding and use of readings on fetal monitors, although experts are not optimistic that the rate of Caesareans will drop.

In cities like New York, Philadelphia and Chicago, as many as 40 percent of babies are delivered by Caesarean. Although it is one of the safest operations, it is not without risk to either mother or baby, and it is far more costly than a natural vaginal delivery.

Nor is it likely that any change in the use of monitors will result in a decrease in babies with cerebral palsy.

As the new practice bulletin explains, monitoring the fetus during labor does not affect the risk of cerebral palsy, because 70 percent of cases occur before labor begins and only 4 percent result solely from a mishap during labor and delivery. The remaining 26 percent of cases can be attributed to a combination of factors that occur before and during labor or after delivery, according to Dr. Macones and other experts who helped develop the guidelines.

Inconsistent Interpretations

How the new guidelines might affect the rate of malpractice cases is unknown. “Lawyers pick through every finding on the tracings and say the doctor should have done a Caesarean here and saved the baby,” Dr. Macones said, “even though that’s seldom the case since most cases of cerebral palsy don’t happen during labor.”

Doctors differ greatly in how they interpret tracings. In a study in which four obstetricians examined 50 fetal heart rate tracings, they agreed in 22 percent of the cases. Two months later, the same four doctors re-evaluated the same 50 tracings and changed their interpretations on nearly one of every five. Furthermore, when the baby’s outcome is already known, interpretation of the tracings is especially unreliable, the guideline report says.

And in more than 99 percent of cases, predictions based on the tracings that the baby would have cerebral palsy have proved wrong.

3 Categories of Tracings

The new guidelines refine the meaning of different readings from the monitors, in the hopes of helping doctors make better decisions during labor about when to intervene and when to let nature take its course.

Previous guidelines divided readings into two categories — reassuring and nonreassuring — and it was up to the doctor to decide whether a nonreassuring reading meant the fetus was at serious risk of oxygen deprivation.

With fear of liability hanging over doctors’ heads, many babies with “nonreassuring” readings who might have done just fine with a natural vaginal delivery are being delivered surgically or with forceps, Dr. Macones said.

The new guidelines divide monitor readings into three categories and help to make “the gray zone of nonreassuring clearer,” Dr. Catherine Y. Spong, chief of the Pregnancy and Perinatology Branch at the child health institute, said in an interview.

In Category I, tracings of the fetal heart rate are normal and no specific action is required.

In Category II, indeterminate tracings require evaluation and continuous surveillance and re-evaluation, the guidelines say. Dr. Spong said that in deciding how serious the tracings are, doctors “need to look at the entire clinical picture, not just the tracing,” and consider factors like the mother’s blood pressure, heart rate and temperature, what medicines she might have been given, the frequency of contractions and how fast labor is progressing.

Depending on what makes the reading Category II, the doctor can take steps to see if the reading will go back to Category I, Dr. Spong said. For example, the doctor might try to stimulate the baby by scratching its scalp or making a loud noise, to see if the heart rate will accelerate naturally and bring the baby back to Category I.

Babies with Category II readings are not considered in danger, she said, “but they have to be watched very closely because they could become compromised.”

In Category III, tracings are clearly abnormal, requiring prompt evaluation and efforts to reverse the abnormal heart rate. That could involve giving the mother oxygen, changing her position, treating her low blood pressure and stopping stimulation of labor if that is being done. If the tracing does not improve with such measures, the new guidelines say that “delivery should be undertaken.”

Further refinements of the guidelines are expected to be released next year.