Pregnancy

Rib Pain in the Third Trimester: Common Causes

Save

Rib pain in the third trimester is usually the uterus lifting and flaring the lower ribs, plus the baby pressing against them. It sits under the bra line, often on the right, and eases with better posture. Steady, severe upper-right pain after 20 weeks is the exception to report.

Last updated: July 2026

Talk to a clinician

Gale can help you find a clinician in your state and request a visit.

Find care →

Why do the ribs hurt so much in late pregnancy?

Rib pain in the third trimester is usually a mechanical result of the uterus pushing up under the ribcage. By about 30 to 36 weeks, the growing uterus can lift the lower ribs and flare them outward, stretching the muscles and cartilage between them, and rising progesterone loosens these joints so they ache more easily.

Pain most often sits on the right side, just under the breast or bra line, and worsens when you slump or hold one position too long. According to antenatal care guidance, aches around the ribs and upper abdomen are among the common, expected discomforts of late pregnancy 1. The pain frequently eases when you stand tall, and it commonly settles once the baby drops lower toward the end of pregnancy.

Is the baby actually kicking my ribs?

Babies do press and kick against the lower ribs, especially once they are large and head-down in the final weeks. A foot or knee lodged under the ribs can produce a sharp, localized jab that comes and goes with movement, which feels different from the constant ache of flared ribs.

Both kinds of rib discomfort are usually harmless. Changing position, leaning forward, or gently encouraging the baby to shift can bring relief. According to prenatal care guidance, your baby's overall movement pattern matters far more for reassurance than the occasional rib jab, and any real drop in movement is what deserves a call 2. Rib soreness by itself rarely signals a problem with the baby.

What eases rib pain in the third trimester?

Position changes and more room for the ribcage relieve most third-trimester rib pain. Sitting upright, using a supportive chair, sleeping propped on pillows, and avoiding slumping all give the lower ribs space to sit naturally.

Gentle stretches that lengthen the side body, shoulder rolls, and the same postural work used for pregnancy back and rib tension can ease the muscle strain. Loose clothing and a well-fitting, non-constricting bra help too. Because a crowded chest also drives late-pregnancy breathlessness and reflux, easing heartburn in pregnancy sometimes lowers the overall pressure under the ribs. Warmth and repositioning are low-risk and usually work within minutes rather than needing medication.

When is upper-belly or rib pain a warning sign?

Most rib pain is musculoskeletal, but pain high on the right side under the ribs is the exception that warrants a call. Steady, severe pain in the upper-right abdomen or the pit of the stomach can be a sign of preeclampsia or a related liver problem.

Preeclampsia is defined by new high blood pressure that appears after 20 weeks of pregnancy, and upper-abdominal pain is one of its warning features 3. According to hypertension-in-pregnancy guidance, this kind of pain often comes with headache, visual changes, sudden swelling, or nausea 4. Musculoskeletal rib pain, by contrast, shifts with position and eases when you move. Pain that is severe, constant, and unrelieved by repositioning is the pattern that should be checked the same day.

When rib pain in pregnancy needs a clinician

Rib pain paired with certain other symptoms is worth a prompt call to your maternity team. On its own, positional rib ache that eases when you sit tall is a normal part of late pregnancy that typically resolves within days to a couple of weeks after birth, once the ribs settle back down.

A clinician can tell ordinary rib flare from the upper-abdominal pain of preeclampsia, check your blood pressure, and reassure you about your baby's movements. First pregnancies and shorter torsos tend to feel rib crowding more. Gale can help you note when the pain started and what makes it better or worse before you call.

Common questions

The uterus often sits or rotates slightly to the right, and the liver is on the right under the ribs, so mechanical rib flare is commonly felt more on that side. Position-related right-sided rib ache that eases when you sit tall is usually benign, but steady, severe upper-right pain is the pattern that should be checked.

Kicks and pressure against the ribs are uncomfortable but do not typically cause harm. Changing position or leaning forward often shifts the baby off the ribs. A sharp jab that comes and goes with movement is different from constant pain, which is worth mentioning.

Not directly. Rib pain reflects how the uterus is sitting and often improves when the baby drops lower into the pelvis in the final weeks, which can happen before labor. It is not a reliable labor sign on its own.

Musculoskeletal rib pain shifts with position, eases when you move or sit tall, and stays around the bra line. Pain that is steady and severe high on the right, or that comes with headache, vision changes, or sudden swelling, is the combination that warrants a same-day call to your maternity team.

Related

Say it back

How would you explain this to someone you love?

Two or three sentences, just as you’d say it. Gale reflects back what you focused on — a mirror, not a quiz.

Talk to a clinician

Gale can help you find a clinician in your state and request a visit.

Find care →

Rib pain in late pregnancy: when to call

  • —Steady, severe pain high on the right side under the ribs or in the pit of the stomach is a reason to seek same-day maternity review for possible preeclampsia.
  • —Rib or upper-belly pain with a headache, vision changes, or sudden swelling of the face and hands is a reason to seek urgent review.
  • —Rib pain with shortness of breath, chest pain, or coughing up blood is a reason to seek emergency care.
  • —A noticeable drop in your baby's movements is a reason to contact your maternity team right away.

If rib or upper-belly pain comes with a severe headache, vision changes, or trouble breathing, contact your maternity unit right away or seek emergency care — these can be signs of preeclampsia or a clot rather than sore ribs.

This article is general health education, not medical advice. Distinguishing ordinary rib flare from the upper-abdominal pain of preeclampsia is a judgment for an obstetric clinician or midwife who can check your blood pressure and your pregnancy.

References

  1. 1.National Institute for Health and Care Excellence (2024). Antenatal care (NG201). National Institute for Health and Care Excellence (NICE). link ✓Antenatal care guidance identifying rib and upper-abdominal aches as common, expected discomforts of late pregnancy
  2. 2.Office on Women's Health (U.S. HHS) (2025). Prenatal care. Office on Women's Health (womenshealth.gov), U.S. HHS. link ✓Prenatal care guidance that monitoring the baby's overall movement pattern is a key reassurance measure and a drop in movement warrants prompt contact
  3. 3.American College of Obstetricians and Gynecologists (2020). Gestational Hypertension and Preeclampsia: ACOG Practice Bulletin, Number 222. Obstetrics & Gynecology. doi:10.1097/AOG.0000000000003891 ✓Practice bulletin defining preeclampsia as new-onset hypertension after 20 weeks and listing upper-abdominal or epigastric pain among its warning features
  4. 4.National Institute for Health and Care Excellence (2023). Hypertension in pregnancy: diagnosis and management (NG133). National Institute for Health and Care Excellence (NICE). link ✓Hypertension-in-pregnancy guidance describing the symptom cluster of upper-abdominal pain with headache, visual disturbance, and swelling that should prompt urgent assessment

4 sources, numbered by first appearance. General health information, not medical advice. AI-assisted editorial content — every citation independently verified. Editorial policy

← Back to the health library