Preterm Labor Signs
Content reviewed against published ACOG, March of Dimes, Mayo Clinic guidelines
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If your baby has been diagnosed with or you suspect preterm labor signs, here is what the evidence says.
The short answer
Preterm labor is labor that begins before 37 weeks of pregnancy and affects about 10% of pregnancies. Recognizing the signs early is critical because treatment can often delay delivery, giving the baby more time to develop. Signs include regular contractions, lower back pain, pelvic pressure, vaginal discharge changes, and fluid leaking. Contact your provider immediately if you suspect preterm labor.
Key takeaways
- Preterm labor is labor that begins before 37 weeks of pregnancy and affects about 10% of pregnancies. Recognizing the signs early is critical because treatment can often delay delivery, giving the baby more time to develop. Signs include regular contractions, lower back pain, pelvic pressure, vaginal discharge changes, and fluid leaking. Contact your provider immediately if you suspect preterm labor.
- Usually normal when: Braxton Hicks contractions that are irregular, infrequent, and stop with rest or hydration
- Call your doctor if: You have regular, painful contractions that are getting closer together and do not stop with rest and hydration before 37 weeks
- Varies by age — see the age-by-age breakdown below
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By Age
What to expect by age
Before 24 weeks
Labor signs before 24 weeks (the threshold of viability) are considered a medical emergency. Warning signs include regular cramping, lower back pain, pelvic pressure, vaginal bleeding, or fluid leaking. If you have risk factors such as prior preterm birth, multiple pregnancy, cervical insufficiency, or uterine abnormalities, your provider may implement preventive measures early in your pregnancy.
24-28 weeks
Between 24-28 weeks, the baby is viable but extremely premature. If preterm labor is suspected, your provider will check your cervix and may perform a fetal fibronectin test. Treatment may include tocolytic medications to slow contractions, corticosteroids to accelerate fetal lung maturity, and magnesium sulfate for neuroprotection. Every additional day in the womb significantly improves outcomes.
28-34 weeks
Preterm labor between 28-34 weeks is managed aggressively to prolong the pregnancy when safe. Corticosteroids are most effective when given at least 24 hours before delivery. Your provider will balance the risks of prematurity against the risks of continuing the pregnancy. Babies born in this window often do well with NICU support but benefit greatly from more time in the womb.
34-37 weeks
Late preterm babies (34-37 weeks) generally do well but may still face challenges with feeding, temperature regulation, and jaundice. Your provider may or may not try to stop labor at this stage depending on the circumstances. Corticosteroids may be given if delivery is expected before 37 weeks. Many late preterm babies go home within a few days of birth.
What Should You Do?
When to take action
- Braxton Hicks contractions that are irregular, infrequent, and stop with rest or hydration
- Occasional mild lower back discomfort or round ligament pain
- Normal increases in vaginal discharge during pregnancy that are not watery or bloody
- Mild pelvic pressure that comes and goes without a pattern
- You are experiencing more than 4-6 contractions per hour before 37 weeks, even if they do not seem painful
- You have a persistent dull lower backache that is different from your usual pregnancy discomfort
- You notice increased vaginal discharge, mucus-like discharge, or slight pink or brown spotting
- You have regular, painful contractions that are getting closer together and do not stop with rest and hydration before 37 weeks
- You have a gush or steady trickle of fluid from your vagina (possible ruptured membranes) before 37 weeks, or vaginal bleeding
Doctor Visit Checklist
Bring this checklist to your next pediatrician visit to discuss Preterm Labor Signs.
Things to mention
- You are experiencing more than 4-6 contractions per hour before 37 weeks, even if they do not seem painful
- You have a persistent dull lower backache that is different from your usual pregnancy discomfort
- You notice increased vaginal discharge, mucus-like discharge, or slight pink or brown spotting
Observations to share
- You are experiencing more than 4-6 contractions per hour before 37 weeks, even if they do not seem painful
- You have a persistent dull lower backache that is different from your usual pregnancy discomfort
- You notice increased vaginal discharge, mucus-like discharge, or slight pink or brown spotting
Urgent signs to report immediately
- You have regular, painful contractions that are getting closer together and do not stop with rest and hydration before 37 weeks
- You have a gush or steady trickle of fluid from your vagina (possible ruptured membranes) before 37 weeks, or vaginal bleeding
My notes
From ismybabyalright.com — free, evidence-based baby health guides
Related Resources
Frequently asked questions
Is preterm labor signs normal?
When should I call the doctor about preterm labor signs?
When is preterm labor signs normal?
What causes preterm labor signs?
What should I mention to my pediatrician about preterm labor signs?
Is preterm labor signs normal at Before 24 weeks?
Is preterm labor signs normal at 24-28 weeks?
Should I go to the ER for preterm labor signs?
Does preterm labor signs go away on its own?
References
- [1]American College of Obstetricians and Gynecologists. Preterm Labor and Birth. ACOG FAQ, 2021. ACOG
- [2]March of Dimes. Preterm labor and premature birth. March of Dimes, 2023. March of Dimes
- [3]Mayo Clinic. Preterm labor - Symptoms and causes. Mayo Clinic, 2023. Mayo Clinic
All content follows our editorial policy and is reviewed against published clinical guidelines.
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Bottom line
Most cases of preterm labor signs are normal. Talk to your pediatrician if you have regular, painful contractions that are getting closer together and do not stop with rest and hydration before 37 weeks.
Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.
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