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Preterm Labor

What is Preterm Labor?

Preterm labor or premature labor is labor that begins before the 37th completed week of pregnancy, which is before the baby is considered to be full term. Full-term is between 38 to 42 weeks. Due dates are usually calculated at 40 weeks from the last menstrual period.

What are the Signs of Preterm Labor?

Each woman may experience premature labor symptoms differently, so call your physician or the OB floor at your hospital if you experience one or more of the following:

  • Uterine contractions, particularly four or more per hour
  • Low, dull backache
  • Menstrual-like cramps
  • Pelvic pressure
  • Intestinal upset
  • Vaginal discharge of blood, mucus or water
  • A feeling that something is not right

Do not wait. Once preterm labor has progressed too far it may be too late to stop it. If you are unsure if you are experiencing labor, go to your clinic or hospital or call 911.

How is Preterm Labor Diagnosed?

Preterm labor involves uterine contractions that open or dilate the cervix. You may also experience premature rupture of membranes (your water breaks).

Your provider may assess you for preterm labor by:

  • Cervical examination to check for dilation
  • Ultrasound
  • Testing for premature rupture of membranes
  • Testing for Fetal Fibronectin (FFN), a protein released by the placenta
  • Monitoring the baby's heartbeat and movement
  • Monitoring contractions

If I go into Preterm Labor, What Happens Next?

Call your doctor or the OB floor at your hospital if you have one or more signs of premature labor. Depending on your symptoms, you may be told to rest and wait for an hour, to drink water and lie down on your left side or to come in to be evaluated.

If you are between 23 and 34 weeks, your health care provider will most likely try to stop preterm labor with medication. In the event that your preterm labor cannot be stopped or if you or your baby's well-being is in danger, the baby may be delivered.

How is Preterm Labor Treated?

Unless you or your baby's health is in danger, your provider may recommend:

  • Medication to temporarily stop the contractions, either orally or by injection or both
  • An injection of steroids to speed up your baby's lung maturity
  • Bedrest or activity restrictions
  • Hospitalization
  • Cervical cerclage (suturing the cervix closed if the preterm labor is caused by cervical incompetency)
  • Antibiotics to fight infection
  • Delivery

What Causes Preterm Labor?

The exact cause of preterm labor is often unknown. Factors may stem from complications from the pregnancy, complications with the fetus or conditions in the mother's body.

Pregnancy factors:

  • Premature rupture of the membranes (amniotic sac – "water breaks")
  • Placental previa (low lying position of the placenta)
  • Placental abruption (the placenta detaches from the uterus)
  • Abnormal and decreased placental function
  • Hydramnios (too much amniotic fluid)

Fetal factors:

  • Multiple gestation (twins, triplets, or more)
  • Fetal behavior that signals distress
  • Erythroblastosis fetalis (Rh/blood group incompatibility)

Maternal factors:

  • Chronic medical illness (such as heart or kidney disease)
  • Preeclampsia (sudden development of high blood pressure, also called toxemia)
  • Abnormal structure of the uterus
  • Cervical incompetence (inability of the cervix to stay closed during pregnancy)
  • History of preterm birth
  • Lifestyle factors, such as smoking, drug or alcohol abuse, stress, domestic violence, long period of standing, exposure to environmental pollutants

How Often Does Preterm Labor Occur?

The March of Dimes reports that 13 percent of births in the United States are preterm births.

  • 71 percent are born between 34 and 36 weeks
  • 13 percent between 32 and 33 weeks
  • 6 percent at less than 28 weeks

What Does it Mean for My Baby?

Preterm labor may result in premature birth (preterm birth) -- when the baby's body and organs are not fully matured. Premature babies are often very small, have low birth weight, problems breathing, eating, staying warm and fighting infection. Babies born before 28 weeks may be too immature to survive outside the womb.

Premature babies often experience:

  • Respiratory problems
  • Cardiovascular (heart) problems
  • Blood and metabolic problems
  • Temperature instability
  • Gastrointestinal problems
  • Neurological problems
  • Infections
  • Long-term health and development issues

Most premature babies will be cared for in a Neonatal Intensive Care Unit for the first few weeks to months after birth.

False Labor or Preterm Labor?

False labor or Braxton Hick's contractions are a normal part of pregnancy. The periodic tightening of the uterus (and your abdomen) are typically painless, but they may be strong enough to take your breath away or force you to stop what you are doing and sit down. Preterm and normal labor may also begin as painless contractions. So, how can you tell the difference?

False Labor

  • Contractions are irregular and do not get closer together over time
  • The cervix does not open
  • Contractions may stop when you lie down or change position

True Labor

  • Contractions may start irregularly, but gradually become regular and closer together
  • The cervix begins to open
  • Labor contractions cannot be stopped by changing positions
  • Labor contractions increase in intensity and pain

Where Can I Find More Information and Support?

Experiencing preterm labor can be frightening and frustrating. Your doctor and hospital can assist you in finding support groups or counselors to help you cope.

You may also visit Sidelines, the National High Risk Pregnancy Support Network.