Most pregnancy symptoms are normal. Some are not. The difficulty is knowing which is which — particularly when your body is doing things it has never done before and the internet offers contradictory reassurance and alarm in equal measure. This article lists the symptoms that require medical attention, organised by when they are most likely to occur. When in doubt, call your provider. No clinician has ever criticised a pregnant woman for calling about a genuine concern.
Any trimester: always call for these
Vaginal bleeding. Light spotting can be normal (particularly in the first trimester after implantation or following a cervical examination), but any bleeding beyond light spotting warrants a call. Heavy bleeding, bleeding with clots, or bleeding accompanied by pain requires urgent assessment. In the first trimester, bleeding affects approximately 25% of pregnancies, and more than half of those pregnancies continue normally — but it needs evaluation to rule out ectopic pregnancy or miscarriage.1
Severe or persistent abdominal pain. Round ligament pain and mild cramping are common. Pain that is severe, one-sided, does not resolve with rest, or is accompanied by bleeding is not normal. In early pregnancy, severe one-sided pain requires assessment for ectopic pregnancy.1
Fever above 38°C (100.4°F). Fever during pregnancy can indicate infection, which may require treatment to protect both mother and baby. Do not assume it is a mild illness and wait it out.2
Painful urination, blood in urine, or back pain with fever. Urinary tract infections are more common in pregnancy and can progress to kidney infection (pyelonephritis) if untreated, which is associated with preterm labour.2
Thoughts of self-harm. Perinatal depression and anxiety can occur at any point during pregnancy or postpartum. If you experience persistent low mood, hopelessness, or thoughts of harming yourself, contact your provider, midwife, or a crisis line immediately. This is a medical symptom, not a personal failing.
First trimester (weeks 1–12)
Severe nausea and vomiting with inability to keep fluids down for 24 hours. This may indicate hyperemesis gravidarum, which can lead to dehydration and requires medical treatment. Weight loss, dark urine, and dizziness alongside persistent vomiting are urgent indicators.3
Severe one-sided pain with or without bleeding. Ectopic pregnancy (where the embryo implants outside the uterus, usually in a fallopian tube) occurs in approximately 1 in 80 pregnancies. It is a medical emergency if the tube ruptures. Shoulder tip pain (caused by internal bleeding irritating the diaphragm) alongside pelvic pain is a red flag requiring immediate emergency assessment.1
Second trimester (weeks 13–27)
Sudden severe swelling of face, hands, or feet. While mild swelling of the feet and ankles is normal, sudden or severe swelling — particularly of the face or hands — can indicate pre-eclampsia. Combined with headache, visual disturbances, or upper abdominal pain, this requires urgent assessment.4
Persistent headache not relieved by paracetamol. In the context of pregnancy, severe or persistent headache, particularly after 20 weeks, requires blood pressure assessment to rule out pre-eclampsia.4
Leaking of fluid from the vagina. This may indicate premature rupture of membranes (PPROM). Even a trickle or sensation of dampness that differs from normal vaginal discharge should be reported, as PPROM requires monitoring and often antibiotics to reduce infection risk.2
Third trimester (weeks 28–40+)
Reduced foetal movement. From 28 weeks, you should be aware of your baby's movement pattern. There is no specific number of movements per day that is "normal" — what matters is your baby's individual pattern. If you notice a significant change — fewer movements than usual, weaker movements, or cessation of movement — contact your provider or maternity unit immediately. Do not wait until the next day. RCOG guidelines recommend lying on your left side and focusing on movements: if you do not feel 10 movements within 2 hours, call your unit.5
Signs of pre-eclampsia. Pre-eclampsia can develop rapidly after 20 weeks and is a leading cause of maternal and perinatal morbidity. Symptoms to call about immediately: severe headache that does not respond to paracetamol; visual disturbances (flashing lights, blurred vision, spots); sudden swelling of face or hands; pain just below the ribs (particularly on the right); and feeling generally unwell. Pre-eclampsia is diagnosed by blood pressure measurement and urine protein testing — you cannot diagnose it at home, but you can recognise the symptoms that trigger urgent assessment.4
Regular contractions before 37 weeks. Braxton Hicks contractions (practice contractions) are irregular, infrequent, and not progressive. Contractions that come at regular intervals, become increasingly painful, and do not stop with rest or hydration may indicate preterm labour and require urgent assessment.2
Sudden gush or persistent trickle of fluid. At term, this may be your waters breaking — which is normal. Before 37 weeks, it may indicate PPROM and requires immediate assessment.
When in doubt
The threshold for calling your provider during pregnancy should be low. Midwives and obstetricians expect calls. Maternity assessment units exist precisely for this purpose. A call that turns out to be nothing costs minutes. A delay in reporting a genuine warning sign can cost much more.
