Preterm labor occurs between the 20th and 37th week of pregnancy. This labor includes both uterine contractions and cervical changes.
A full-term pregnancy lasts 38-42 weeks but preterm labor can lead to early delivery. Infants born before 37 weeks are considered premature.
In most cases, the cause is of preterm labor is unknown.
Some preterm labor is associated with preterm premature rupture of membranes (PPROM). PPROM is the rupture of both the amniotic sac and chorion membranes. It generally occurs at least 1 hour before labor begins.
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The chance of preterm-labor is greatest in women under the age of 18 years or over 35 years. Other maternal factors that may increase the chance of preterm labor include:
Pregnancy complications that may increase your risk of preterm labor include:
Other factors associated with an increased chance of preterm labor include:
- History of 1 or more spontaneous second-trimester miscarriages
- Less than 6 months between giving birth and the beginning of the next pregnancy
- A previous preterm birth
- Abnormally shaped uterus
- Previous weight reduction surgery
- Procedures to remove abnormal cervical cells
Symptoms may include:
- Abdominal pain that feels something like menstrual cramps
- Dull pain in the lower back
- Pressure in the pelvis and tightening in the thighs
- Vaginal bleeding or spotting, or watery discharge
You will be asked about your symptoms and medical history. A physical exam will be done. Your doctor may recommend tests to check your cervix and membranes have ruptured. An
will help your doctor see internal structures and the baby.
Fluids in the cervix will also be tested for sign of labor progression. A tocometer may be placed to help monitor contractions.
Treatment will depend on your baby's development, especially the growth of the lungs. If your doctor believes the baby is ready, the labor may be allowed to continue. If the baby is not ready to be delivered, your doctor may try to stop the labor. Stopping labor is a complicated process and may not always work.
Some treatment options may include:
- Tocolytics—may delay labor for a few days
- Corticosteroids—to help the baby's lungs develop
- Antibiotics—if an infection is suspected or present
To help reduce your chance of preterm labor:
- Get the proper prenatal care throughout your entire pregnancy.
- Eat a healthy, balanced diet with plenty of fruits, vegetables, and whole grains.
- Consider adding fish to your diet. It may reduce the risk of preterm birth.
- Drink plenty of water.
- Avoid smoking, alcohol, and drugs.
- Keep chronic diseases under control.
- Stay active during your pregnancy. Your doctor can give you exercise guidelines that are right for you.
- If you are at high-risk for premature birth, talk to your doctor about progesterone therapy or cervical cerclage, a procedure that closes the cervix with sutures.
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