Preterm Labor
Condition
Definition
Preterm labor is labor that starts before 37 weeks. It can lead to early delivery. Babies born before 37 weeks are premature.
Causes
The cause is not always known. Sometimes it is caused by preterm premature rupture of membranes (PPROM). This is when the amniotic sac breaks before 37 weeks and labor has not started within 1 hour.
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Risk Factors
This problem is more common in women who:
- Are Black
- Are pregnant with more than one baby
- Used assistive reproductive technology to become pregnant
- Are under the age of 16 years old
Some things that may raise the risk are:
- Prior premature birth
- Problems with the cervix
- Certain infections
- Substance use
- Alcohol use
- Mental health problems, such as depression or anxiety
- Problems with the placenta or uterus
- Vaginal bleeding
- Birth defects in the fetus
Symptoms
Problems may be:
- Belly cramps with or without diarrhea
- Watery or bloody vaginal discharge
- An increase in discharge
- Dull pain in the lower back
- Pressure in the pelvis and tightening in the thighs
Diagnosis
The doctor will ask about symptoms and health history. An exam will be done. This is often enough to make the diagnosis.
Treatment
Treatment will depend on the baby's growth, especially the lungs. Labor may be allowed to go on in a baby that is more developed. The doctor may try to stop labor in a baby that is not developed enough.
Some ways this may be treated are with:
- Tocolytics to try to delay labor for a few days
- Corticosteroids to help the baby's lungs grow
- Antibiotics to treat an infection
Prevention
This problem cannot always be prevented. Early and regular prenatal care can help find and treat some problems before they happen.
American Congress of Obstetricians and Gynecologists
American Pregnancy Association
CANADIAN RESOURCES:
The Society of Obstetricians and Gynaecologists of Canada
Women's Health Matters
American Congress of Obstetricians and Gynecologists
American Pregnancy Association
CANADIAN RESOURCES:
The Society of Obstetricians and Gynaecologists of Canada
Women's Health Matters
References
- American College of Obstetricians and Gynecologists’ Committee on Practice Bulletins—Obstetrics. Practice Bulletin No. 171: Management of Preterm Labor. Obstet Gynecol. 2016 Oct;128(4):e155-64, reaffirmed 2018.
- Premature and preterm labor. American Pregnancy Association website. Available at: http://americanpregnancy.org/labor-and-birth/premature-labor.
- Preterm labor. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/preterm-labor.
- 7/15/2016 DynaMed Systematic Literature Surveillance. https://www.dynamed.com/condition/preterm-labor: Saccone G, Berghella V, et al. Celiac disease and obstetric complications: a systematic review and metaanalysis. 2016;214(2):225-234.
Contributors
- Elizabeth Margaret Prusak, MD
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