Health Topic

Preterm Labor

Preterm labor is labor that begins before the 37th week of pregnancy. Learn what signs to look for in a preterm labor such as cramps or bleeding.

Reviewed Reviewed by a registered pharmacistGeneral information

Also called: Early Labor · Premature Birth · Premature Labor · Preterm Birth

Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.

About Preterm Labor

Preterm labor is labor that starts before 37 completed weeks of pregnancy. It can lead to premature birth. Premature babies may face serious health risks.

Symptoms of preterm labor include:

  • Contractions every 10 minutes or more often
  • Leaking fluid or bleeding from the vagina
  • Feeling of pressure in the pelvis
  • Low, dull backache
  • Cramps that feel like menstrual cramps
  • Abdominal cramps with or without diarrhea

If you think you might be having preterm labor, contact your health care provider.

It sits within Female Reproductive System.

The lead U.S. institute for this subject is the Eunice Kennedy Shriver National Institute of Child Health and Human Development.

When to speak to someone. Reading about a topic cannot tell you whether it applies to you. Speak to a doctor or pharmacist if symptoms are severe, sudden, getting worse, or simply not going away — and seek emergency care immediately for chest pain, breathing difficulty, sudden weakness or confusion, or a serious allergic reaction.

Research on Preterm Labor

2,777 studies areregistered for this condition on ClinicalTrials.gov, the U.S. National Library of Medicine's public registry. A selection is below — the links go straight to the registry entry, not to a summary of ours.

What a registered study does and does not mean. Registration means a study exists and has been declared publicly. It says nothing about whether the treatment being tested works, is safe, or is available to you. Many studies find no benefit — that is what research is for. Never seek out an experimental treatment on the strength of a registry entry alone.

Research currently under way

Research already completed

Study data from ClinicalTrials.gov, a service of the U.S. National Library of Medicine. Retrieved 2026-07-30. Registry entries are supplied by study sponsors and investigators; ClinicalTrials.gov does not verify their scientific validity. PocketsInfo is not affiliated with, and not endorsed by, the NLM or the NIH.

Where to read more

Rather than paraphrase, we point you to the primary sources. Every link below is to a government health agency, a national institute or a recognised medical body — grouped by what you are trying to find out.

Learn More

Clinical Trials

Medical subject headings

Clinicians and researchers index this subject under Obstetric Labor, Premature. These are the terms to use when searching medical literature.

This page is built from the MedlinePlus health topic record for Preterm Labor, a service of the U.S. National Library of Medicine (NLM), National Institutes of Health. Information is from MedlinePlus.gov. PocketsInfo is not affiliated with, and is not endorsed by, the NLM or the NIH. Retrieved 30 July 2026.