McKesson Clinical Reference Systems: Women's Health Advisor 2002.2

What is preterm labor?

If you have regular, painful uterine contractions and changes in your cervix between your 20th and 36th weeks of pregnancy, you are having preterm labor. It is also called premature labor.

Preterm labor can lead to delivery of a premature baby. A premature baby faces many challenges. A premature baby may require special treatment in an intensive care nursery or could die at birth. Even with intensive treatment, the premature baby may die or may have chronic lung disease or other serious problems.

Preterm labor can sometimes be controlled with bed rest or medication and does not always result in premature delivery of the baby. Follow all of your health care provider's instructions very carefully so that your baby can be born in the best condition possible.

How does it occur?

Preterm labor seldom has a recognizable cause.

You have a greater risk of preterm labor if:

• You do not see your health care provider regularly while you are pregnant.
• You have preeclampsia (a condition of high blood pressure, water retention, and protein in the urine).
• You have premature rupture of your membranes (your bag of waters has broken).
• You had a previous preterm labor or delivery.
• You are pregnant with more than one baby.
• You have surgery on the abdomen during the pregnancy, such as removal of your appendix.
• You have far too little or too much fluid in the amniotic sac (the bag of waters) surrounding the baby.
• You have vaginal bleeding after 16 weeks of pregnancy.
• You have an abnormally shaped uterus.
• You have fibroids inside your uterus.
• Your mother took the drug DES when she was pregnant with you.
• You are less than 18 years old.
• You have had kidney or bladder infections.
• You have placental abruption (early separation of the placenta from the wall of the uterus).
• You do physically strenuous work and work long hours, causing much fatigue.
• You smoke during your pregnancy.
• You use controlled substances or street drugs.
• You have infection in the cervix or uterus.
• You have a sexually transmitted disease.
• You have had one or more second-trimester abortions.
• You have an incompetent cervix (your cervix opens too early).

What are the symptoms?

Preterm labor contractions may be more subtle than and feel different from normal labor contractions. Many times a preterm labor contraction is hard to distinguish from the normal aches and pains of pregnancy and movements of the baby. It is important to know the signs and symptoms of preterm labor, how to feel the uterus for contractions, and when to call your health care provider about contractions.

Some of the signs and symptoms of preterm labor are:

• an increase or change in vaginal discharge
• any rhythmic pelvic pressure
• menstrual-like cramps that come and go
• abdominal cramps with or without diarrhea
• backache with a tightening of the abdomen.

If you are at risk for preterm labor, call your health care provider if you have any unusual sensations, pains, or aches.

How is it diagnosed?

Your health care provider reviews your symptoms and does a pelvic exam to see how much your cervix has thinned or dilated. Your provider may use a uterine monitor to measure and time uterine contractions.

How is it treated?

Your health care provider may or may not try to stop labor and premature delivery of your baby. The decision is based on how long you have been pregnant, your and the baby's health, the availability of an intensive care nursery, changes in your cervix, and whether or not your membranes have ruptured.

The longer your pregnancy continues, the better the chances are that the baby will survive. It also usually reduces the amount of time your baby will spend in the intensive care nursery.

If you are at risk for preterm labor and delivery, you may be treated for preterm labor even if your cervix has not yet thinned or dilated.

Treatment for stopping preterm labor includes:

• staying in the hospital
• continuous uterine monitoring
• bed rest (lying on the left side is best for uterine relaxation and blood flow)
• intravenous (IV) fluid to which a drug may be added to stop contractions
• lab tests of blood, urine, and cells from the cervix to look for infection
• ultrasound to check the condition of the placenta, to check the baby's age, to look for any birth defects, to see the position of the baby in your uterus, and to measure the amount of fluid in the amniotic sac
• amniocentesis to look for infection or to see if the baby's lungs are mature
• cervical cerclage (surgically closing the cervix) if your cervix is opening too early.

Medications used to stop preterm labor can be given orally or into a vein (IV). Usually one medication is started with an IV. Later you may switch to pills.

Your health care provider will probably not use a drug to stop premature birth if:

• You have a lot of vaginal bleeding.
• You have very high blood pressure.
• You have an infection in your uterus.
• You have a baby with fatal birth defects or who has died already.
• You have any condition in which the pregnancy should not go on.

If it appears that your preterm labor may go on into full labor and delivery, your health care provider may give you corticosteroids to help the baby's lungs mature. The medicine will help your baby breathe better after delivery. Corticosteroids are usually given only if you are between the 24th and 34th weeks of pregnancy and you are going into full labor.

How can I take care of myself and help prevent preterm labor?

If you are at increased risk for preterm labor:

• Visit your health care provider as soon as you think you are pregnant.
• Visit your health care provider according to the schedule you are given and follow all of your provider's advice.
• Discuss with your health care provider possible effects of your work schedule.
• Rest as much as possible.
• Don't skip meals. Eat healthy meals and snacks every day.
• Learn how to recognize contractions by feeling your uterus with your hand on your abdomen. Check for contractions of your uterus regularly at home. Record the contractions on a chart.
• Learn about other signs and symptoms of premature labor. Call your health care provider if you have any signs or symptoms of preterm labor or any unusual feelings.
• Avoid stimulation of your nipples (which can cause contractions).
• Avoid intercourse if orgasm or intercourse causes contractions.

If you are being treated for preterm labor, carefully follow all of your health care provider's instructions.

This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.