Braxton Hicks Contractions

Braxton Hicks contractions are irregular, painless or mildly uncomfortable uterine tightenings that do not cause cervical change and are often called false labour.

• They occur from early pregnancy but are usually felt from about 20 weeks, becoming more frequent in the third trimester.
• They are thought to prepare the myometrium for labour.
• They are commoner with dehydration, a full bladder, physical activity, sexual intercourse and in multiparous women.
• They do not progress and do not dilate or efface the cervix.

They are irregular, short and non-progressive.

• Irregular tightening of the abdomen lasting 30 to 60 seconds (rarely up to 2 minutes).
• Intervals vary and do not become shorter or stronger over time.
• Often relieved by rest, walking, a change of position, drinking water or a warm bath.
• Felt mostly in the lower abdomen and front of the uterus rather than the back.
• No show, fluid leakage, bleeding, or change in fetal movements.
• Differential diagnosis: true labour, preterm labour, placental abruption, urinary tract infection, chorioamnionitis, dehydration-related irritability, and uterine fibroid pain.
• Complications: none directly. Misdiagnosis may lead to unnecessary admission or, conversely, missed preterm labour.

Diagnosis is clinical, with objective exclusion of preterm labour when before 37 weeks.

• History of irregular, non-progressive tightenings and a soft, non-tender uterus between episodes.
• Vaginal examination (when appropriate) shows a closed, uneffaced cervix.
• Cardiotocography shows irregular contractions with a reactive fetal heart rate.
• Before 37 weeks with regular contractions: cervical length by transvaginal ultrasound, and fetal fibronectin where available.
• Urinalysis to exclude infection. Check temperature and blood pressure.

Treatment is reassurance and non-drug measures.

• Supportive: explain that the contractions are normal. Drink at least 2 litres of water daily, empty the bladder often, rest on the left side, avoid prolonged standing, take a warm bath, and practise slow breathing.
• Pharmacological: none usually required. Paracetamol 500 mg to 1 g every 6 hours as needed (maximum 4 g in 24 hours) if uncomfortable.
• Procedures: none.
• Special groups: before 37 weeks, regular contractions (four or more in an hour) need assessment for preterm labour. Women with a history of preterm birth or short cervix need closer review.
• Red flags: regular painful contractions every 5 to 10 minutes that intensify, vaginal bleeding, leaking fluid, reduced fetal movements, fever, constant abdominal pain or a hard tender uterus.
• Follow-up: routine antenatal care. Advise return if contractions become regular, stronger or closer together.