July 23, 2001 -- From cancer to diabetes to heart disease, medical advances have been impressive over the past few decades. But there is one area where doctors have not made as much progress -- preventing preterm labor.
For many reasons -- increasing maternal age, rising rates of multiple births thanks to advances in fertility -- the rate of early deliveries has risen sharply in the U.S., with an increase of 23% in the past 20 years.
"The national controversy is what to do about it," says Fung Lam, MD, chief of gynecology and vice chairman of obstetrics and gynecology at California Pacific Medical Center in San Francisco. "The pendulum is swinging back and forth, and currently the national view that's holding sway is that interventions are not successful."
'A Major, Major Problem'
Each day in the United States, 1,239 babies are born preterm -- that is, less than 37 weeks into the pregnancy. A normal pregnancy lasts 40 weeks after the first day of the last menstrual period. Infants born early are more likely to be low weight and suffer complicated health problems including underdeveloped lungs. They are 13 times more likely to die in their first year of life than other newborns.
"It is still a major, major problem," says James Martin Jr., MD, president of the Society for Maternal Fetal Medicine and director of maternal-fetal medicine at the University of Mississippi Medical Center in Jackson.
"The thrust of a lot of research is to better diagnose the patient at risk and to intervene effectively ... so baby can safely remain in utero for a longer amount of time," Martin tells WebMD.
And it's expensive. Consider that neonatal intensive care units cost at least $3,000 per day, and preterm infants who survive spend many weeks or months there.
Exactly why it occurs is not fully understood, but women are more likely to experience preterm labor or deliver prematurely if they have done so in the past, are carrying multiple babies, and/or have certain medical conditions that can complicate pregnancy.
"Doctors get a failing grade at how well we understand the process, and we are not much better at treatment," says Stephen Chasen, MD, director of high-risk obstetrics at New York Weill-Cornell Center.
The Pharmaceutical Approach
"For practical purposes, the cut-off most people use is 34 weeks for treating preterm labor," Chasen says. Between 34 and 37 weeks, complications of prematurity are rare, so doctors don't necessarily employ aggressive treatment, he says.
"The most important thing is to give steroids to accelerate the maturity of the baby should he or she be born," he says. "Giving steroids can decrease lung complications or brain complication and decrease mortality."
A type of medications called tocolytic agents may be used to stop the whole labor process and let the pregnancy progress. They include terbutaline, which relaxes the uterus and decreases contractions, but this drug has not been officially approved for preterm labor. Another drug, ritodrine, was pulled from the market when the FDA required further testing and the company declined to bear the cost of further studies.
Magnesium sulfate may also be used to disrupt the communication that allows muscles to contract. It is usually given through an intravenous infusion into the arm. The heart drug Procardia may also be used to decrease contractions by blocking the muscle's communication system.
"These medications can delay delivery long enough for steroids to have beneficial effects," Chasen says. Another drug, Antocin, is in the FDA pipeline.
The Home-Monitoring Approach
Sometimes women at high risk of preterm labor will choose home uterine monitoring, which is basically a belt they strap on twice a day for an hour each time. While the pregnant woman is wearing the belt, she will push a button on it every time she thinks she feels a contraction. The information is then transmitted to her doctor.
The emergence of these home-monitoring devices rubs many professionals the wrong way.
"The bottom line is that no one has demonstrated that it leads to healthier pregnancies or delivery at a later gestational age," Chasen says.
Lam, however, says they're a fine way to keep tabs on things and to alert the woman if she needs medical attention.
"You use a thermometer to take someone's temperature to see if they have a fever, and if they do, you have to treat them because the thermometer won't cure the fever," he says. "The same is true with home uterine monitoring. It's a diagnostic tool, not a therapeutic tool."
Janet Bleyl is an advocate of home uterine activity monitoring. "We have thousands of women who have known early on they're having preterm labor because of home monitoring," says Bleyl, founder and president of the Triplet Connection, a Stockton, Calif.-based nonprofit group for families who have had or who are expecting triplets or more.
"We have seen lots of patients in preterm labor who, due to drugs and aggressive treatment, have prolonged their pregnancy from weeks to months," she tells WebMD.
Because of the insidious nature of premature labor, "women who find themselves in it are unable to detect it themselves, which is why home monitoring can be so important and useful," she says.
What to Watch For
Women should be on the lookout for:
- Mild uterine contractions
- Low back pain or pelvic heaviness
- Increased pink or brown vaginal discharge or vaginal discharge with foul odor
"Realize that preterm labor is not painful," Bleyl says. "Most are watching for painful contractions, but if they are in a high-risk situation even minor contractions are big news and need to be checked out. Most often it can be stopped or helped if doctors intervene early enough.