Preterm Labor Signs
Preterm labor — contractions and cervical changes occurring before 37 weeks of pregnancy — affects about 10% of pregnancies. Recognizing the early signs allows for timely medical intervention to delay delivery and improve outcomes.
What "Severe" Means Here
A "severe" rating means this symptom can sometimes signal an underlying condition that needs medical evaluation, even though it can also occur as an intense but ultimately benign version of a common pregnancy symptom. The safest approach is not to try to self-diagnose which case you’re in — contact your provider to describe what you’re experiencing so they can assess it properly, rather than waiting to see if it resolves on its own. Even if you’re fairly confident it’s "just" an intense version of something normal, providers would generally rather evaluate a severe symptom in person or over the phone than have a patient manage it alone at home.
Timing During Pregnancy
This symptom is most often reported later in pregnancy. Third-trimester symptoms are frequently related to the growing uterus placing more pressure on nearby organs, joints, or blood vessels, or to the body preparing for labor. Because late-pregnancy symptoms can occasionally overlap with signs of labor or other conditions specific to the third trimester, it’s worth reviewing the "when to call your doctor" guidance below a bit more closely as your due date approaches. Many providers also schedule more frequent visits in the third trimester specifically so that new or worsening symptoms can be caught and addressed quickly.
Common Causes
- Uterine infection or inflammation
- Premature rupture of membranes (water breaking before labor)
- Cervical insufficiency (weakened cervix)
- Multiple gestation (twins, triplets)
- Placenta previa or placental abruption
- Prior preterm birth (strongest risk factor)
- Short cervical length identified on ultrasound
- Urinary tract infection or sexually transmitted infection
Remedies That May Help
Go to the Hospital Immediately
If you suspect preterm labor, this is an emergency. Go to the hospital — do not wait to see if symptoms resolve.
Progesterone Supplementation (Preventive)
For women with a prior preterm birth or short cervix, progesterone supplementation reduces recurrence risk.
Cervical Cerclage (Preventive)
For women with cervical insufficiency, a stitch placed in the cervix (cerclage) can help prevent premature dilation.
Corticosteroids (Hospital Treatment)
If preterm labor is occurring between 24–34 weeks, steroids are given to accelerate the baby's lung maturation.
When to Call Your Doctor
- Regular uterine contractions (more than 4–6 per hour) before 37 weeks
- Lower back pain or pelvic pressure that comes and goes rhythmically
- A gush or trickle of fluid from the vagina (possible ruptured membranes)
- Pinkish or bloody vaginal discharge (bloody show)
- Significant change in vaginal discharge — more mucus, watery, or tinged with blood
- A feeling that 'something is different' — trust your instincts
Warning Signs That Always Warrant Immediate Care
Regardless of the specific symptom you’re looking up, general ACOG and CDC guidance is to seek immediate medical attention — call your provider’s urgent line, go to labor and delivery, or go to the ER — if you experience any of the following:
- Vaginal bleeding that is heavy, bright red, or accompanied by pain
- Severe or persistent abdominal or pelvic pain
- A severe headache that doesn’t improve with rest, water, or over-the-counter pain relief
- Sudden swelling of the face, hands, or feet, especially paired with a headache or vision changes
- Vision changes such as blurring, seeing spots, or temporary vision loss
- A noticeable decrease in your baby’s movement compared to their usual pattern
- Fever of 100.4°F (38°C) or higher
- Fluid leaking or gushing from the vagina
- Regular, painful contractions before 37 weeks
- Difficulty breathing, chest pain, or a rapid heartbeat
- Persistent vomiting that keeps you from keeping down fluids
- Severe itching, especially on the palms and soles, which can sometimes indicate a liver-related condition
This list reflects general warning signs recognized across pregnancy, not just for this specific symptom — when in doubt, it’s always appropriate to call your provider and describe what you’re experiencing rather than waiting to see if it resolves.
General Tips for Managing Pregnancy Symptoms
Alongside any symptom-specific remedies above, a handful of general habits tend to help with a wide range of pregnancy symptoms and are worth keeping in mind throughout your pregnancy:
- Stay consistently hydrated — many pregnancy symptoms, from headaches to fatigue to constipation, are worsened by even mild dehydration.
- Keep taking your prenatal vitamin as directed, since nutrient gaps (particularly iron, calcium, and vitamin D) can compound certain symptoms.
- Prioritize rest and sleep where you can, including resting on your side in later pregnancy, which supports circulation to the uterus.
- Stay gently active if your provider has cleared you for exercise — light movement like walking or prenatal yoga can ease many common complaints.
- Eat smaller, more frequent meals rather than three large ones, which can help with digestive symptoms and blood sugar swings.
- Keep a running list of questions between appointments so nothing gets forgotten when you do see your provider.
None of these general habits replace medical evaluation for a specific concerning symptom, but they’re a reasonable baseline to maintain throughout pregnancy regardless of what you’re experiencing.
Frequently Asked Questions
How do I tell preterm labor contractions from Braxton Hicks?
Braxton Hicks are irregular, don't get stronger or more frequent, and often stop with hydration and rest. Preterm labor contractions are regular (every 10 minutes or less), get stronger over time, and don't stop with rest or water.
What should I do if I think I'm in preterm labor?
Call your provider or go to labor and delivery immediately. Do not wait to see if symptoms resolve on their own. Time matters — early intervention can delay delivery.
Can preterm labor be stopped?
In some cases, tocolytic medications can delay labor by 24–48 hours — enough time to administer steroids for the baby's lungs. Stopping preterm labor entirely for weeks is rarely possible.
What is premature rupture of membranes (PROM)?
PROM is when the amniotic sac ruptures before the onset of labor. When it occurs before 37 weeks it is called preterm PROM (PPROM) and is a medical emergency requiring immediate hospital evaluation.
Will I know if my water breaks?
You may feel a sudden gush of warm fluid, or a slow trickle. Amniotic fluid is clear to light yellow and may be hard to distinguish from urine — when in doubt, go to the hospital.
How do I know if a pregnancy symptom needs medical attention?
As a general rule, contact your provider if a symptom is severe, sudden, rapidly worsening, or paired with other concerning symptoms like fever, vision changes, or reduced fetal movement — even if it doesn’t appear on a specific warning-signs list. You know your body best, and providers consistently say they’d rather field a call about something that turns out to be normal than have a patient wait through something that wasn’t.
Should I track this symptom before my next appointment?
It’s a good habit to jot down when a symptom started, how often it occurs, roughly how intense it feels, and anything that seems to make it better or worse. This kind of record is genuinely useful to your provider — it turns a vague "I’ve been having some discomfort" into something they can actually assess for patterns, and it can help you notice on your own whether a symptom is improving, staying steady, or getting worse over time.
Is it normal for pregnancy symptoms to come and go?
Yes — many pregnancy symptoms fluctuate day to day or even hour to hour, influenced by things like hydration, activity level, meal timing, and simple positional changes. Fluctuation on its own usually isn’t a red flag. What’s more worth flagging to your provider is a symptom that is steadily trending worse over days or weeks, or one that suddenly becomes much more intense than your usual pattern.