Premature Labor
Pregnancy usually lasts about 40 weeks, but sometimes it could be cut short because of premature labor. Here's what you need to know about it.
Most pregnancies — around 90 percent of them — last 40 weeks (or
more, if you're overdue), though a pregnancy is considered full-term
once you reach the 37-week mark. Still, more and more expectant women
these days (around 10 percent) find that their expected nine months of
pregnancy has turned into an unexpected seven or eight months of
pregnancy because they go into labor too early. Preterm or premature
labor is labor that occurs after week 20 of pregnancy (it's considered a
miscarriage before that) and before week 37.
What Accounts for the Rise in Rates
How can it be with today's advanced medical technology that the rate of premature labor and delivery is on the rise? In part, it's due to that advanced technology. The increase in successful fertility treatments has led to a rise in multiples — and multiples are more likely to arrive early. The increasing age at which women are having babies these days (thanks again to that advanced medical know-how) is also contributing to the rising statistics, since older woman are more likely to deliver prematurely.
How can it be with today's advanced medical technology that the rate of premature labor and delivery is on the rise? In part, it's due to that advanced technology. The increase in successful fertility treatments has led to a rise in multiples — and multiples are more likely to arrive early. The increasing age at which women are having babies these days (thanks again to that advanced medical know-how) is also contributing to the rising statistics, since older woman are more likely to deliver prematurely.
Risk Factors for Preterm Birth
But new technology and older moms certainly don't account for all
preterm births. There are a number of other risk factors too — some
that are preventable, some that aren't. In the preventable camp are
factors such as very low prepregnancy weight (though if you make up that
weight during the pregnancy, the risk of preterm labor goes down), not
gaining enough weight during pregnancy (ditto), smoking, cocaine use, or
alcohol use during pregnancy (a risk factor easily preventable — just
quit!), or an untreated sexually transmitted disease, such as gonorrhea
or chlamydia (the risk for preterm birth goes down considerably once the
STD is treated). Even the nonpreventable risk factors (such as a low
socioeconomic level, being African-American, having a previous preterm
birth, or having pregnancies very close together) can be mitigated with
good prenatal care and healthy lifestyle habits.
Most important to remember, however, is that having one of these
risk factors doesn't mean that you'll definitely go into premature
labor. Similarly, not having any of the risk factors doesn't mean that
you won't go into premature labor (some women go into premature labor
for reasons other than those associated with risk factors, and other
women go into premature labor for no known reason).
What Might Cause It
Six factors that might be at play in too-early labor
No one knows for sure what actually causes premature labor, but
experts are able to point to a number of factors that could play a role
in triggering your uterus to begin contracting and your cervix to begin
dilating way before your baby is ready to come out.
Uterine and vaginal infection: Infections, both those in the genital tract — such as bacterial vaginosis (BV) — and those in the uterus and amniotic fluid, are thought to be responsible for nearly half of all preterm births. Experts suspect that such infections cause inflammation, which in turn leads to the release of prostaglandins — the same substance that initiates labor when you're full-term. Untreated urinary-tract infections can also cause preterm labor.
Pregnancy complications: Complications such as gestational diabetes, preeclampsia, excessive amniotic fluid, as well as problems with the placenta, such as placenta previa or placental abruption, can make an early delivery more likely.
Structural anomalies of the uterus and/or cervix: A uterus that is malformed, extremely large, or has other structural abnormalities can make it more difficult to carry a baby to term — as can problems with the cervix (such as an incompetent cervix — when the cervix doesn't stay closed the way it's supposed to during pregnancy — or a short cervical length).
Gum infections: Periodontal disease, which expectant moms are more susceptible to because of the effects of pregnancy hormones, has been linked to preterm labor. Some experts suspect that the bacteria that cause inflammation in the gums can actually get into the bloodstream, reach the fetus, and initiate early delivery. Other research proposes another possibility: The bacteria that cause inflammation in the gums can also trigger the immune system to produce inflammation in the cervix and uterus, triggering early labor.
Stress levels: Researchers theorize that severe emotional stress can lead to the release of hormones that in turn trigger uterine contractions and preterm labor.
Occupational factors: Extreme physical stress on the job has also been linked to preterm labor. Researchers have found that women who stand for long periods of time (more than five hours a day) or who have jobs that are extremely physically exhausting are more likely to deliver early.
Uterine and vaginal infection: Infections, both those in the genital tract — such as bacterial vaginosis (BV) — and those in the uterus and amniotic fluid, are thought to be responsible for nearly half of all preterm births. Experts suspect that such infections cause inflammation, which in turn leads to the release of prostaglandins — the same substance that initiates labor when you're full-term. Untreated urinary-tract infections can also cause preterm labor.
Pregnancy complications: Complications such as gestational diabetes, preeclampsia, excessive amniotic fluid, as well as problems with the placenta, such as placenta previa or placental abruption, can make an early delivery more likely.
Structural anomalies of the uterus and/or cervix: A uterus that is malformed, extremely large, or has other structural abnormalities can make it more difficult to carry a baby to term — as can problems with the cervix (such as an incompetent cervix — when the cervix doesn't stay closed the way it's supposed to during pregnancy — or a short cervical length).
Gum infections: Periodontal disease, which expectant moms are more susceptible to because of the effects of pregnancy hormones, has been linked to preterm labor. Some experts suspect that the bacteria that cause inflammation in the gums can actually get into the bloodstream, reach the fetus, and initiate early delivery. Other research proposes another possibility: The bacteria that cause inflammation in the gums can also trigger the immune system to produce inflammation in the cervix and uterus, triggering early labor.
Stress levels: Researchers theorize that severe emotional stress can lead to the release of hormones that in turn trigger uterine contractions and preterm labor.
Occupational factors: Extreme physical stress on the job has also been linked to preterm labor. Researchers have found that women who stand for long periods of time (more than five hours a day) or who have jobs that are extremely physically exhausting are more likely to deliver early.
How to Prevent It
Doing your best to keep your baby in its uterine home until it's ready to face the world
As good as your chances are of carrying to term (and they're
excellent!), there's always more you can do to help keep your baby put
until he or she is completely ready for a healthy and timely arrival:
Eliminate the bad. Quit smoking, drinking, or using drugs. Watch your weight.Gaining too much weight during pregnancy can up your odds of developing gestational diabetes and preeclampsia, both of which increase preterm labor risk. Gaining too little weight during pregnancy is another significant risk factor (as well as a risk factor for a baby born too small). Aim for the right gain (for the average woman — 25 to 35 pounds) and you'll greatly improve your chances of delivering a full-sized baby at full term.
Take your prenatal vitamins. Not only will that one pill a day enhance your overall health and that of your growing baby, but it'll also improve the odds that you'll carry to term. It doesn't take the place of a balanced diet, but it's insurance that every pregnant woman should invest in.
Eat well. That balanced diet is good for you, for your baby, and for your pregnancy. And here's yet another reason why: Making sure you get the right mix of nutrients can help prevent preterm labor — with extra special mention going to omega-3 fatty acids (found in salmon, DHA eggs, walnuts, and flax seed), vitamins A (enjoyed in carrots, apricots, and broccoli), C (look to citrus, berries, bell peppers), and E (noshed on in nuts, sweet potatoes, and mangoes), calcium (get milk and other dairy products or fortified juices), magnesium (enjoy in beans, tofu, yogurt, dried apricots, bananas, and sesame seeds), iron (get your share from beef, dried fruit, and soy products), zinc (found in turkey, pork, beef, oatmeal, corn, cooked oysters, and eggs), and the famously baby-friendly folic acid (added to most grain products, found naturally in bananas, oranges, and green leafies). (See The Pregnancy Diet.)
Eat often. Research suggests that it's not enough to ship your baby all the right nutrients — you should also make those shipments as regular as possible. Pregnant women who eat at least five times a day (three meals and two snacks, or five smaller meals, for instance) are less likely to deliver prematurely.
Drink up. Getting your eight glasses of fluids a day (more if you're exercising or it's very hot) will keep you hydrated — and staying hydrated increases your odds of keeping baby put. Dehydration can lead to premature contractions.
Be good to your gums. Preventative dental care is one of your first (and best, and easiest) lines of defense in preventing preterm labor, which can be triggered by gum disease. So brush, floss, and visit your dentist at least once during your pregnancy — not just for your regular cleaning, but also to take care of any little problems before they become big ones.
Go when you gotta go. Holding in your urine, besides being uncomfortable, can inflame your bladder — which in turn could irritate your uterus and set off contractions. Not going when you gotta go could also lead to a urinary tract infection, another cause of preterm contractions. So make a habit of peeing when you've got the urge to go.
Treat it. If you're considered high-risk because you have BV (bacterial vaginosis), ask your practitioner if an oral antibiotic is right for you. Some studies show that symptomatic women with BV who are treated with antibiotics have a reduced risk of preterm delivery. Other studies, though, have disputed those findings, saying that there is no reduction in the rate of premature delivery even if the infection (both BV and other STDs) is treated. Your practitioner will be able to best guide you.
Explore your options. Exciting new research is finding that the hormone progesterone reduces the risk for preterm birth in women with a prior history of one. If you've had a previous preterm birth, ask your practitioner if you're a good candidate for progesterone injections.
Test for it. There are two screening tests that may be useful in predicting whether you're at risk for preterm birth. Right now, these tests are only recommended for high risk women since positive test results aren't an accurate predictor of early delivery (but negative results can help avoid unnecessary interventions — and needless anxiety).
The first is fetal fibronectin (fFN), a test that detects a protein in the vagina only present if there have been uterine contractions. If you have a negative fFN test, it's unlikely you'll go into preterm labor within the next few weeks (so you can breathe easy). If it's positive, your risk of going into preterm labor is significantly high — but the good news is that your practitioner will likely take steps to prevent a preterm birth.
The second screening test is for cervical length. Via ultrasound, the length of your cervix is measured, and if there are any signs that the cervix is shortening or opening, your practitioner may take some steps to prevent early labor — such as putting you on bed rest or perhaps stitching your cervix closed. But before your practitioner gives you a cerclage, as this stitching procedure is called, talk to him or her about recent studies that have found that a cerclage isn't effective in preventing preterm labor as was once believed.
While it's far more likely that your baby will arrive late than early (and remember, 90 percent of women carry to term), it's smart to know the signs of premature labor, just in case. The earlier you recognize that you're in labor, the earlier you'll be able to seek treatment for it. Call your practitioner right away if you are experiencing these symptoms:
Eliminate the bad. Quit smoking, drinking, or using drugs. Watch your weight.Gaining too much weight during pregnancy can up your odds of developing gestational diabetes and preeclampsia, both of which increase preterm labor risk. Gaining too little weight during pregnancy is another significant risk factor (as well as a risk factor for a baby born too small). Aim for the right gain (for the average woman — 25 to 35 pounds) and you'll greatly improve your chances of delivering a full-sized baby at full term.
Take your prenatal vitamins. Not only will that one pill a day enhance your overall health and that of your growing baby, but it'll also improve the odds that you'll carry to term. It doesn't take the place of a balanced diet, but it's insurance that every pregnant woman should invest in.
Eat well. That balanced diet is good for you, for your baby, and for your pregnancy. And here's yet another reason why: Making sure you get the right mix of nutrients can help prevent preterm labor — with extra special mention going to omega-3 fatty acids (found in salmon, DHA eggs, walnuts, and flax seed), vitamins A (enjoyed in carrots, apricots, and broccoli), C (look to citrus, berries, bell peppers), and E (noshed on in nuts, sweet potatoes, and mangoes), calcium (get milk and other dairy products or fortified juices), magnesium (enjoy in beans, tofu, yogurt, dried apricots, bananas, and sesame seeds), iron (get your share from beef, dried fruit, and soy products), zinc (found in turkey, pork, beef, oatmeal, corn, cooked oysters, and eggs), and the famously baby-friendly folic acid (added to most grain products, found naturally in bananas, oranges, and green leafies). (See The Pregnancy Diet.)
Eat often. Research suggests that it's not enough to ship your baby all the right nutrients — you should also make those shipments as regular as possible. Pregnant women who eat at least five times a day (three meals and two snacks, or five smaller meals, for instance) are less likely to deliver prematurely.
Drink up. Getting your eight glasses of fluids a day (more if you're exercising or it's very hot) will keep you hydrated — and staying hydrated increases your odds of keeping baby put. Dehydration can lead to premature contractions.
Be good to your gums. Preventative dental care is one of your first (and best, and easiest) lines of defense in preventing preterm labor, which can be triggered by gum disease. So brush, floss, and visit your dentist at least once during your pregnancy — not just for your regular cleaning, but also to take care of any little problems before they become big ones.
Go when you gotta go. Holding in your urine, besides being uncomfortable, can inflame your bladder — which in turn could irritate your uterus and set off contractions. Not going when you gotta go could also lead to a urinary tract infection, another cause of preterm contractions. So make a habit of peeing when you've got the urge to go.
Treat it. If you're considered high-risk because you have BV (bacterial vaginosis), ask your practitioner if an oral antibiotic is right for you. Some studies show that symptomatic women with BV who are treated with antibiotics have a reduced risk of preterm delivery. Other studies, though, have disputed those findings, saying that there is no reduction in the rate of premature delivery even if the infection (both BV and other STDs) is treated. Your practitioner will be able to best guide you.
Explore your options. Exciting new research is finding that the hormone progesterone reduces the risk for preterm birth in women with a prior history of one. If you've had a previous preterm birth, ask your practitioner if you're a good candidate for progesterone injections.
Test for it. There are two screening tests that may be useful in predicting whether you're at risk for preterm birth. Right now, these tests are only recommended for high risk women since positive test results aren't an accurate predictor of early delivery (but negative results can help avoid unnecessary interventions — and needless anxiety).
The first is fetal fibronectin (fFN), a test that detects a protein in the vagina only present if there have been uterine contractions. If you have a negative fFN test, it's unlikely you'll go into preterm labor within the next few weeks (so you can breathe easy). If it's positive, your risk of going into preterm labor is significantly high — but the good news is that your practitioner will likely take steps to prevent a preterm birth.
The second screening test is for cervical length. Via ultrasound, the length of your cervix is measured, and if there are any signs that the cervix is shortening or opening, your practitioner may take some steps to prevent early labor — such as putting you on bed rest or perhaps stitching your cervix closed. But before your practitioner gives you a cerclage, as this stitching procedure is called, talk to him or her about recent studies that have found that a cerclage isn't effective in preventing preterm labor as was once believed.
How to Recognize It
Was that a routine ache or cramp, or something more ominous? Here are the signs of premature labor.
While it's far more likely that your baby will arrive late than early (and remember, 90 percent of women carry to term), it's smart to know the signs of premature labor, just in case. The earlier you recognize that you're in labor, the earlier you'll be able to seek treatment for it. Call your practitioner right away if you are experiencing these symptoms:
- Regular contractions coming every ten minutes (or more often) that do not subside when you change position. Braxton Hicks contractions (practice contractions that are irregular, don't intensify, and subside when you change position) are not cause for concern. If you're not sure, call your practitioner anyway.
- Fluid leaking from your vagina (make sure it's not urine by taking the sniff test. If it smells like ammonia, it's urine. If it doesn't, it could be amniotic fluid.)
- Cramps in the lower abdomen or lower back.
- A significant increase in pressure in the pelvic area.
- A change in your vaginal discharge to blood-streaked.
- Vaginal bleeding.
What to Expect If You Experience It
Here's what's likely to happen if you go into labor before your baby is ready to be born.
If you're experiencing any symptoms of premature labor, your
practitioner will want to assess you, either in the office or (more
likely) in the hospital. You can expect the following.
Premature Labor Tests
If You're in Premature Labor
If your practitioner thinks you might be in labor, you can expect the following to occur, depending on how far along in the pregnancy you are and what other complications you may be having:
Babies born before 34 weeks will almost always need to stay in the NICU (neonatal intensive care unit) for a few weeks or months. Babies born between 34 and 37 weeks of gestation who have no other health problems generally do fine — and often only need a short stay in the NICU before they head home. Join the Moms of Preemies group to meet other members who have experienced preterm labor.
Premature Labor Tests
- You'll be hooked up to a fetal monitor to check for contractions and to make sure the baby is not in any distress.
- Your practitioner will probably use a vaginal swab to test for signs of infection and possibly fetal fibronectin. You might also receive an ultrasound to assess the amount of amniotic fluid and to confirm the size and gestational age of your baby.
- Your cervix will be examined to determine if any dilation or effacement has begun.
If You're in Premature Labor
If your practitioner thinks you might be in labor, you can expect the following to occur, depending on how far along in the pregnancy you are and what other complications you may be having:
- If you haven't yet been tested for Group B strep (the test is usually performed after 35 weeks), you'll be given IV antibiotics to prevent transmission of the bacteria to your baby in case you are indeed a carrier.
- You may be administered tocolytic agents, such as magnesium sulfate, which relax the uterus and (theoretically, at least) stop contractions. These medications are usually only dispensed if you're less than 34 weeks pregnant and if your baby's lungs are deemed too immature for delivery.
- If your baby's lungs are still immature, corticosteroids will be administered to speed fetal lung maturity.
Babies born before 34 weeks will almost always need to stay in the NICU (neonatal intensive care unit) for a few weeks or months. Babies born between 34 and 37 weeks of gestation who have no other health problems generally do fine — and often only need a short stay in the NICU before they head home. Join the Moms of Preemies group to meet other members who have experienced preterm labor.
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