Round ligament pain is a sharp or aching sensation in the lower belly or groin that happens when the ligaments supporting your uterus stretch during pregnancy. It most commonly shows up during the second trimester, between weeks 14 and 27, when the uterus is growing rapidly. It’s one of the most common pregnancy complaints, and while it can be startling, it’s generally harmless.
What the Round Ligament Actually Is
The round ligaments are two cord-like bands of tissue that attach to the upper corners of your uterus, near where the fallopian tubes connect. From there, each ligament travels through the abdominal wall, passes through your groin via a small channel called the inguinal canal, and eventually inserts into the labia. Their job is to hold the uterus in position.
Outside of pregnancy, these ligaments are firm and relatively short. As the uterus expands to accommodate a growing baby, the round ligaments stretch significantly, getting both wider and longer. That increased tension is what causes pain, and it can radiate through the entire groin area rather than staying in one small spot.
What It Feels Like
The hallmark of round ligament pain is a quick, sharp, stabbing sensation on one or both sides of the lower abdomen or groin. It often hits the right side more than the left, partly because of the way the uterus tends to tilt as it grows. Some people describe it as a pulling or stretching feeling rather than a stab, and it can also present as a dull ache that lingers after a period of activity.
Episodes are usually brief. A sharp jab may last only a few seconds, though a duller soreness can persist for several minutes or longer after a triggering movement. The pain does not come and go in regular, rhythmic waves the way contractions do.
Common Triggers
Round ligament pain is almost always set off by sudden movement. Rolling over in bed, standing up quickly, laughing, coughing, or sneezing are classic triggers because they cause an abrupt tug on the already-stretched ligament. Exercise, long walks, and even just a busy day on your feet can bring on the duller, achy version of the pain. The common thread is any motion or position that puts extra pull on the ligament before it has time to adjust.
Why the Second Trimester
The uterus undergoes its most dramatic growth spurt between roughly 14 and 27 weeks. Before that, it’s still small enough to sit low in the pelvis without putting much tension on the ligaments. After the second trimester, the ligaments have typically stretched enough to accommodate the uterus’s size, and the rate of expansion slows. That’s why most people notice round ligament pain peaking in the middle months of pregnancy, though it can occasionally start earlier or linger into the third trimester.
Ways to Ease the Discomfort
Because the pain comes from mechanical stretching, the most effective strategies are ones that reduce sudden tension on the ligaments. Moving slowly and deliberately when you change positions, especially when getting out of bed or standing from a chair, gives the ligaments time to adjust rather than snapping taut. If you feel a sneeze or cough coming, bending your hips slightly or bracing your lower belly with your hand can cushion the pull.
A pregnancy support belt worn under the belly can offload some of the weight the ligaments carry, which helps on days when you’re on your feet a lot. Gentle stretching, particularly pelvic tilts and cat-cow movements on all fours, keeps the surrounding muscles flexible and can reduce how often pain flares up. Sleeping on your side with a pillow between your knees takes pressure off the pelvis and is generally the most comfortable position from the second trimester onward.
Warm (not hot) baths or a heating pad on a low setting placed against the sore side can relax the ligament and surrounding muscle. Acetaminophen is considered safe during pregnancy for occasional pain relief, though it’s worth confirming the right dose with your provider. Anti-inflammatory painkillers like ibuprofen are typically avoided during pregnancy.
When the Pain Signals Something Else
Round ligament pain is brief, triggered by movement, and resolves on its own. Certain patterns suggest the discomfort may have a different cause. Pain that comes at regular intervals, gradually gets stronger, or doesn’t go away with rest could indicate preterm contractions. Pain accompanied by fever, chills, vaginal bleeding, or pain during urination may point to an infection, placental issue, or urinary tract problem.
Severe, constant pain in the lower abdomen, especially if it’s on one side and started early in pregnancy, can be a sign of an ectopic pregnancy or ovarian cyst. And if the pain is paired with nausea, vomiting, or changes in vaginal discharge, it warrants prompt evaluation. The key distinction is that true round ligament pain is transient and clearly linked to a specific movement. Anything that doesn’t fit that pattern is worth a call to your care team.