Round Ligament Pain in Pregnancy

What is actually happening

The HSE explains the anatomy in one line: "The round ligament connects your womb to your pelvis." As your womb expands, the ligaments stretch, and the result is "pain in your lower tummy, groin or hips on one or both sides."

The NHS calls the same thing "ligament pain (often called 'growing pains' as the ligaments stretch to support your growing bump)". It is the most common explanation for the sharp, short pains that appear once the bump starts to make itself felt.

The HSE frames it as characteristic of the second trimester, which matches when most people first notice it — the womb is growing fast enough to put the ligaments under real tension, but not yet large enough for the later mechanical problems to dominate.

What it feels like

Tommy's description is the most specific: "sharp pains on both sides of your stomach (tummy), which get worse when you move." It characterises the pain as usually sharp or stabbing.

The triggers are what make it recognisable:

• Sudden movements — standing up quickly, or rolling over in bed.
• Sneezing, coughing or laughing.
• Changing position.

The duration is the other giveaway. It is a stab, not a build. It arrives with the movement and fades within seconds to a minute or two. Tommy's is reassuring on the substance: "Round ligament pains will not harm you or your baby and are nothing to worry about."

What it is not

Most of the anxiety around this symptom comes from mistaking it for something else, so it is worth setting out the alternatives explicitly.

It is not a contraction

Braxton Hicks are a tightening across the whole bump, not a stab in one spot. Tommy's characterises them as "often irregular (more than 10 minutes apart), short-lasting, uncomfortable more than painful." They come and go and, crucially, do not build up. Round ligament pain is tied to a movement; a contraction is not.

It is not the same as pelvic girdle pain

Pelvic girdle pain is felt over the pubic bone, lower back, hips or buttocks, often with clicking or grinding, and is triggered by weight-bearing — walking, stairs, standing on one leg, turning in bed. It tends to be an ongoing ache with movement-related flares, rather than a momentary stab.

It may be constipation or trapped wind

Both are extremely common. Tommy's reports that constipation affects around 40 in every 100 pregnant people, and that "there are treatments that are safe to take in pregnancy, so if lifestyle changes such as drinking more water and eating more fibre do not help, contact your GP." The NHS notes that mild pain which improves when you change position, rest, open your bowels or pass wind is generally harmless.

What actually helps

The HSE gives three specific measures for round ligament pain:

• Lie on the opposite side to the pain.
• Take your time when moving, especially when turning in bed at night.
• Take a warm bath.

To that, a practical extension of the same principle: because the pain is triggered by sudden loading, bracing before a sneeze or cough — bending slightly and supporting the bump — follows directly from the mechanism. Be aware, though, that this is a sensible inference rather than something a national body has tested. There are no trials of treatment for round ligament pain, and you should be wary of anyone who implies otherwise.

What the guidance does not support is doing less. Both the NHS and RCOG advice for pregnancy-related musculoskeletal pain is to stay active while avoiding the specific movements that hurt, rather than to rest completely.

When to call

Contact your GP, midwife, maternity unit or hospital if:

• The pain is severe, or mainly on one side. The HSE flags this specifically, because appendicitis can present this way in pregnancy and is easily attributed to ligaments.
• The pain is severe or does not go away after you have rested for 30 to 60 minutes (NHS).
• You have vaginal bleeding or spotting.
• You have regular cramping or tightenings.
• You have unusual vaginal discharge, or fluid leaking.
• You have lower back pain that is not usual for you.
• You have pain when you pee, are peeing more often than usual, or your urine is cloudy, pink, red or brown.
• You have a temperature of 38°C (100.4°F) or above. The NHS notes a high temperature can be a sign of infection and needs checking.
• Your baby's movements change or reduce.

The HSE adds two further prompts to contact your midwife, GP or obstetrician immediately: "one of your calves is red, swollen and hot", and "you have a severe headache — especially with other symptoms including blurred vision, upper stomach pain, nausea or swelling."

Call your local emergency number (999 in the UK and Ireland, 911 in the US and Canada, 000 in Australia, or 111 in New Zealand) or go to an emergency department if you have sharp, sudden, intense tummy pain together with feeling very dizzy or faint, heavy bleeding, or collapse.

If you are under 37 weeks

Lower the threshold. The NHS lists regular contractions or tightenings, period-type pains, a gush or trickle of fluid, and backache that is not usual for you as reasons to call your midwife or maternity unit before 37 weeks — and adds that you can call "if you're unsure or worried about anything." Rhythmic pain is never round ligament pain.

The honest summary

Round ligament pain is defined by three features together: it is sharp, it is brief, and it is tied to a movement. Pain that lacks any one of those — a dull ache that will not go, a pain that persists at rest, a pain that arrives rhythmically without you moving — is worth a phone call, not a search for reassurance.