My patient needed to be delivered. She had just developed eclampsia, a potentially fatal disease that afflicts women in the second half of pregnancy. She had suffered a seizure and dangerously high blood pressure, and was at risk for far worse, including a stroke. No one knows why this condition arises, but delivery sure clears it up in a hurry.

So we gave medication to start labor, and the nurses placed a fetal heart monitor.

Worn like a belt, but higher on the abdomen, the ultrasound monitor would play a crucial role in the hours to come. It prints a read-out strip of the baby’s heart rate, and the pattern would guide us in determining whether the delivery would be natural or through cesarean section.

As I suspected, the baby’s heart-rate strip showed worrisome changes soon after labor began, and I knew it would get worse as labor progressed. We would fight through the night to have a natural delivery. But ultimately that single heart-rate test, which is surprisingly unreliable, would be a key factor in whether my patient would get a C-section or not.

Nearly all American mothers are monitored during labor, and bad fetal heart strips are an important cause of high cesarean section rates. A recent report detailed the dizzying increases: Almost one in three babies was delivered by cesarean in 2007, the most recent year for which data are available. That rate has grown by more than 50 percent in a decade.

I have performed hundreds of cesarean sections during residency, and many were the result of bad heart-rate strips.

A jagged pattern indicating increases in the heart rate reassures us that the baby’s brain is awake and alert, and that labor could continue. But a flat line or decreases in the heart rate after contractions make us think the baby is not getting enough oxygen and pushes us to do a C-section – delivering the baby through incisions in the abdominal wall and the uterus.

For the worst readings, we believed every second counted and rushed the surgery: If the baby wasn’t delivered one minute from the first incision into the skin, we had moved too slowly.

The complication we feared most was hypoxia, the baby not getting enough oxygen during labor. Going too long without adequate oxygen could result in a serious permanent injury, such as cerebral palsy, or even death.

No test is perfect. But almost every time we whisked a mother back to the operating room, and I cut through skin, fat, fascia, and finally the muscle of the uterus, expecting a blue, floppy baby, the child I delivered emerged pink, healthy, and a little bit angry.

Were we saving lives and averting disaster? Or were we performing unnecessary surgery?

Fetal heart-rate monitoring is a screening test. Good tests get several things right; they are cheap, detect a possible problem when there is still time to act, and minimize unnecessary follow-up tests.

Fetal heart monitoring is an appallingly poor test. The test misses the majority of babies with cerebral palsy, the condition researchers hoped it would prevent. It causes increased rates of a painful and expensive surgery: cesarean section. Even worse, almost all women undergo continuous heart monitoring during labor, not just those at highest risk.

Why do doctors cling to continuous fetal heart monitoring? An obstetrician will likely point to the fear of being sued, but the complete answer is more complex. Our medical culture prizes technology and tests, even if they don’t work and can cause harm. “It’s our bias that anything that can be quantified is an improvement,” said H. Gilbert Welch, a professor at Dartmouth Medical School whose research focuses on harm caused by screening and over-diagnosis.

“I think we get in trouble when we start promising things to . . . well [patients],” Welch said in an interview. “It is not that hard to make them worse.”

Throughout the night, I struggled with my patient’s bad fetal heart strip. I wanted her to avoid a cesarean section. To improve the strip, the nurses and I tried giving her oxygen, changing her position in the bed, even rubbing the baby’s head through the cervix to wake it up.

Finally, at 3 a.m., I felt compelled to recommend cesarean. The strip continued to look bad, and my patient’s labor progressed slowly.

We went to the operating room, and delivered the baby by cesarean. My patient’s child greeted the world pink and well-oxygenated.

The test was wrong again.

Alexander Friedman is a fellow in maternal-fetal medicine at the University of Pennsylvania.

Costs of Care has launched its annual 2011 healthcare essay contest, with the goal of expanding the national discourse on the role of doctors, nurses, and other care providers in controlling healthcare costs.  The contest will solicit stories from care providers and patients across the nation that illustrate everyday opportunities to curb unnecessary and even harmful health care spending on a grassroots level. 

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