Abdominal pain in pregnancy: a case-based approach

The presentation

"Priya" (an illustrative example) is 30 and phones her maternity unit one afternoon. She is unsure exactly how many weeks pregnant she is — her period was late and a home test was positive about six weeks ago. Since this morning she has had a cramping pain low down on one side and some light brown spotting. She feels a little dizzy when she stands. The midwife listens carefully to three things at once: how far along the pregnancy is, where the pain sits and how it behaves, and whether there is any bleeding or feeling faint. Early pregnancy with one-sided pain, spotting and dizziness raises a specific worry that shapes everything that follows.

Ruling out the dangerous causes first

Good clinicians work from worst-case backwards. In early pregnancy, the standout concern is an ectopic pregnancy — where the pregnancy grows outside the womb, usually in a fallopian tube. It can cause one-sided tummy pain, unusual bleeding, shoulder-tip pain and faintness, and if the tube ruptures it becomes a life-threatening emergency. That is why Priya is advised to go straight to an early pregnancy unit or A&E. Later in pregnancy, a different set of serious causes matters: pre-eclampsia, placental problems, preterm labour, and appendicitis. Because pregnancy changes where organs sit and masks some usual signs, clinicians keep a low threshold for investigating and never assume pain is "just stretching".

The common, less worrying causes

Most tummy pain in pregnancy turns out to be benign. Round ligament pain — sharp or dragging aches low down or in the groin — comes from the ligaments supporting the growing womb stretching, and is common in the middle months. Trapped wind, constipation and heartburn are very frequent because pregnancy hormones slow the gut. Braxton Hicks contractions are painless or mildly uncomfortable tightenings that come and go and are not true labour. Urinary infections are also common and can cause lower tummy pain and stinging when passing urine. These causes are reassuring, but a clinician still checks the story fits and that there are no red flags hiding underneath a seemingly ordinary ache.

Assessment and next steps

Assessment blends the story with simple checks. The team asks about the pattern of pain, bleeding, waters, the baby's movements later in pregnancy, and symptoms of pre-eclampsia such as headache, vision changes and sudden swelling. They check blood pressure and test the urine for protein and signs of infection. In early pregnancy, an ultrasound scan and blood tests help locate the pregnancy and rule out an ectopic. Later on, monitoring the baby's heartbeat and the mother's blood pressure guides decisions. The plan depends entirely on the findings — many people are reassured and sent home with safety-netting advice, while others need admission, scans or urgent treatment. The key is not guessing but getting properly checked.

Safety-netting and when to seek help

Whatever the likely cause, everyone is given clear safety-netting. In pregnancy you should contact your maternity unit, GP or NHS 111 urgently if you have severe or constant tummy pain, one-sided pain with dizziness or shoulder-tip pain, any vaginal bleeding, a gush or trickle of fluid, or a fever. Signs of pre-eclampsia — a bad headache, seeing flashing lights or blurring, sudden swelling of the face, hands or feet, or pain just below the ribs — need same-day assessment. Reduced or changed baby movements should always be checked, day or night. Trust your instincts: maternity teams would far rather see you and reassure you than have you wait at home worrying.