Pregnancy can feel eternally long—40 weeks (which is actually 10 months, not nine!). But sometimes something goes awry, and the baby decides they want to come out early. Dangerously early. Although many women fear going into labor and giving birth early, it’s actually not all that common: In 2016, 9.6 percent of births were preterm, and 75 percent of those happened between 32 and 36 weeks.
What is premature labor?
A pregnancy is considered preterm before 37 weeks’ gestation. “Technically, premature labor is defined as uterine contractions, which cause cervical change,” explains Sara Twogood, MD, OB-GYN, and assistant professor at the Keck School of Medicine of the University of Southern California. In other words, if your contractions are causing your cervix to change—meaning dilation or effacement are taking place—and you are not yet 37 weeks along, then this is considered preterm.
What premature labor signs should I be looking out for?
As your pregnancy progresses, you should be looking out for uterine contractions with cervical change. There’s a difference between having Braxton Hicks, or false, contractions (which won’t lead to labor) and having contractions that are actually leading to labor. How can you tell the difference? “This varies from woman to woman, but I usually describe Braxton Hicks contractions as only being in the uterus. In fact, sometimes you actually feel a tightening of the uterus. You may see your abdomen change shape, and it might be uncomfortable. If you palpate your abdomen, the uterus feels firm. But a few minutes later, it feels soft.” Braxton Hicks are irregular and unpredictable. They go away with rest and hydration. As anyone who has given birth will tell you, labor contractions are painful—and they become more painful with time, as well as (usually) more predictable. In other words, you know when the next one is coming, since they are approximately 5–6 minutes apart (and grow more frequent). “Labor may start in the back or low pelvis and travel forward,” explains Twogood. “They feel like severe menstrual cramps. They are more painful, and won’t go away with hydration and rest.” Women often have terrible back pain, especially if they’re having back labor. The key is to differentiate between the two. “If we catch preterm labor early, it’s easier to stop,” says Twogood. “So it’s easier to stop dilation that is 1 cm than 8 cm. We don’t want women ignoring contractions thinking they’re Braxton Hicks, but we don’t need them coming in for them.” As for cervical change, this, too, can be hard to know and will usually require an evaluation. “Your mucus plug can pass anywhere from 6 weeks to 6 minutes before delivery,” says Twogood, “so it’s not a good gauge.” It can also pass multiple times during pregnancy, so losing it at 35 weeks does not necessarily indicate that labor is imminent. In the hospital, your OB will check your cervix, if it’s safe. More specifically, she will check the Bishop score: effacement, dilation, consistency of the cervix, position of the cervix, and fetal station (how far up the birth canal the baby is stationed). She’ll also check your cervical length—how long the cervix is. This gives her (and you) a sense of how far off labor might be. If you score below a 5, you’re not close yet. Always call your doctor if you feel that something is off, but remember that Braxton Hicks are quite common, especially in the late stages of pregnancy.
Can bed rest prevent preterm labor?
“Hydration and rest can help ease Braxton Hicks contractions,” Twogood explains. “Hydrating with IV fluids can also help decrease or minimize labor contraction, but it won’t stop preterm labor.” Bed rest is a management strategy that might bring more blood to the placenta, but it unfortunately does not change outcomes. Twogood explains that doctors and patients use it because it makes sense intuitively—rest, decreased stress, and diminished pressure on the cervix doesn’t hurt. But bed rest does have its own risks: muscle and bone weakness, increased risk for deep vein thrombosis (or blood clot), increased anxiety or depression, and musculoskeletal and cardiovascular deconditioning. It’s becoming more popular to instead move to modified activity, or activity restriction, rather than complete bed rest. If a patient is admitted to the hospital for preterm labor, she is monitored continuously, which also limits activity. These restrictions depend on both patients and physicians, but in general, if you are at home and not in the hospital, and you are at risk of going into preterm labor, you can abide by the one-thing-a-day rule:
- One trip to the grocery store or one outside activity but no more.
- No heavy lifting.
- Not being on your feet for more than a few hours per day.
- Limited work (depending on the type of work).
- Minimized stress.
I think I might be in preterm labor. When should I go to the hospital?
One thing is certain: If your water breaks, go straight to the hospital, because there are different treatment and management guidelines when that happens. Additionally, if you’re experiencing any bleeding or consistent, heavy contractions, contact your doctor, who can help you decide if you should head to the hospital.
What causes preterm labor?
There are a few ways to tell whether you might be at risk for preterm labor:
- A history of preterm labor. “This is by far the biggest risk factor,” explains Twogood. “The earlier the preterm labor (say 24 weeks vs. 36½ weeks) puts a woman at higher risk for having another episode of preterm labor.” It’s important to distinguish between preterm labor and preterm birth—the former does not always lead to the latter. Preterm labor leading to preterm birth will put you in the highest risk group.
- Smoking and/or drug use. “Almost every bad outcome is linked to those two factors,” says Twogood.
- An infection. Kidney infections or appendicitis during pregnancy can increase your risk for preterm labor. You can also develop an infection in the uterus or amniotic cavity. This is treated slightly differently because in those cases, the baby can be infected as well.
- Stress. This one is complicated because women often assume stress is the culprit for preterm labor, but stress itself is not necessarily a risk factor. It all depends on your physiological response to stress: If it increases cortisol levels, causes changes in your diet (food and drink), or creates lifestyle alterations—these can predispose you to preterm labor. “That said, different women respond differently to stress,” says Dr. Twogood. “Some life event in one woman might not cause any physiological changes in another woman. It’s so variable from one woman to the next. I don’t want them to think they can’t work! Work has actually been shown to be healthy for pregnancy. Stress can’t cause preterm labor. It does cause physiological changes, but it is not a source of preterm labor.”
What happens if I go into preterm labor?
If you go into preterm labor, your doctor may try to stop it with medications called tocolytics that can only be administered in the hospital. If your baby is not yet 34 weeks, you’re identified as higher risk, so in addition to medications to stop contractions, doctors also administer antenatal corticosteroids to the mom to help the baby’s lungs mature. In case the baby is born, the baby will do better than without the steroids.
How can preterm labor (and premature birth) affect mom and baby?
This depends almost entirely on how early a baby is delivered. A preemie born at 36 weeks and 6 days will do better than a baby born at 28 weeks. “Before 34 weeks, you can expect the baby to be hospitalized,” says Twogood. “There is also potential for all sorts of complications. The baby will need to stay in the hospital for monitoring weight gain/loss, bowel function, and brain development, among other things.” Preterm birth can also, of course, impact nursing. “If the baby is hospitalized with tubes and not feeding well, this can really affect how mom is connecting to baby,” she says. “This can predispose her to postpartum depression, especially if she’s neglecting to care for herself. Women who’ve had babies in NICU have a different experience than having baby in the room with you and going home a few days later.” An early birth is often accompanied by a slew of complications, which are exacerbated the earlier the baby is born. Other than being quite small, the baby might have difficulty breathing and regulating temperature and a lack of reflexes to suck or nurse. The baby may have heart problems (low blood pressure or heart complications), brain problems (because of possible brain bleeds), blood problems (anemia and/or jaundice), and gastrointestinal problems (because the system is underdeveloped). The immune system is also compromised. Preemies often develop into healthy kids, but some can suffer long-term effects, such as cerebral palsy, hearing or vision problems, impaired learning ability, and compromised immune systems.
When it comes to preterm labor, trust your body.
Pregnancy is a trip, but it’s a chance to get to know your own body: Does this contraction feel like it did last week? Yesterday? Does drinking water and sitting down help? Or do I really feel like my body is going into labor? If you feel like something is off, then reach out to your provider. You know your body best. Trust your gut.