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Preterm Labor

What is preterm labor?

Preterm (premature) labor occurs when the uterus contracts and your cervix opens earlier than normal. The cervix is the opening of your uterus. In preterm labor, contractions are strong enough and often enough to allow the cervix to open for delivery of your baby. Preterm labor happens after the 20th week of pregnancy but before the 37th week of pregnancy. An early labor could cause you to have your baby before he is ready to be born.

What causes preterm labor?

The cause is sometimes unknown. The following may cause early labor:

  • Abnormal uterus: A large uterus or a short cervix can cause you to go into labor early.

  • Chronic illness: Illnesses such as high blood pressure, diabetes, or obesity can cause early labor.

  • Infection: Urinary tract infections or vaginal infections can weaken the membranes (linings) of the amniotic sac around your baby. This could lead to premature rupture of the membranes and preterm labor.

  • Problems with the placenta: Problems with the placenta, such as placenta previa or placental separation, may cause preterm labor. The placenta is the tissue that joins you to your baby.

  • Trauma: Injury to your abdomen or uterus may also cause some cases of preterm labor.

What increases my risk for preterm labor?

  • You are pregnant with 2 or more babies.

  • You are under 17 or over 35 years of age.

  • You get pregnant again less than 6 months after delivery.

  • You had a preterm labor or preterm birth in the past.

  • You did not have prenatal care.

  • You smoke, drink alcohol, or use street drugs while pregnant.

  • You are underweight. Too little weight gain during pregnancy may also increase your risk for early labor.

What are the signs and symptoms of preterm labor?

You may not know that you are having preterm labor. It is common to have preterm contractions (tightening and relaxing of the uterus) and not notice them. The following are signs and symptoms that suggest a preterm labor:

  • Abdominal pain or pain that feels like menstrual cramps

  • Changes in vaginal discharge, such as more discharge or discharge that is watery or bloody

  • Low back pain

  • Pressure in the lower abdomen

  • Vaginal spotting or bleeding

How is preterm labor diagnosed?

You may have one or more of the following tests to check for preterm labor:

  • Pelvic exam: This is also called an internal or vaginal exam. During a pelvic exam, your caregiver will gently put a warmed speculum into your vagina. A speculum is a tool that opens your vagina. This lets your caregiver see if your cervix is opening.

  • Vaginal ultrasound: During this test, a small tube is placed into your vagina. Sound waves will show pictures of your cervix and your baby inside your uterus. Your caregiver will be able to see the pictures on a TV-like screen. This test will help your caregiver see if your cervix is opening.

  • Fetal ultrasound: This test uses sound waves to show pictures of your baby inside your uterus. Your caregiver will rub gel on your abdomen and move a small, handheld tool through the gel. As this is done, pictures of your baby can be seen on a TV-like screen. Caregivers will look at your baby's movement, heart rate, and position.

  • Fetal fibronectin test: This test checks for a protein called fetal fibronectin in the cervix or vagina. Normally, there is no protein in cervical and vaginal secretions from the 20th week of pregnancy until near the end.

How is preterm labor treated?

Early treatment may delay delivery. You may need any of the following:

  • Bed rest: You may need to drink lots of fluids and rest in bed on your left side, which improves circulation to the uterus. Your caregiver will tell you when it is okay to get out of bed.

  • Medicines:

    • Tocolytics: Tocolytics are given to stop contractions if your baby is not ready to be born. Contractions are when the muscles of your uterus tighten and loosen.

    • Antibiotics: This medicine is given to help treat or prevent an infection caused by bacteria.

    • Corticosteroids: These medicines may be given if your preterm labor cannot be stopped and your caregiver thinks you may deliver the baby early. These medicines help your baby's lungs mature to prevent him from having breathing problems after birth.

What are the risks of preterm labor?

Preterm labor may cause you to have your baby before he is ready to be born. Your baby could have lung problems and other serious problems if he is premature.

When should I contact my caregiver?

Contact your caregiver if:

  • You have abdominal cramps, pressure, or tightening.

  • You have a change in vaginal discharge.

  • You have burning when you urinate or you are urinating less.

  • You have questions or concerns about your condition or care.

When should I seek immediate care?

Seek care immediately or call 911 if:

  • Your baby's umbilical cord is hanging out of your vagina.

  • You have bright red, painless vaginal bleeding.

  • Your symptoms do not get better or are getting worse.

  • Your water broke or you feel warm water gushing or trickling from your vagina.

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your caregivers to decide what care you want to receive. You always have the right to refuse treatment. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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