Pregnancy

Third Trimester: Weeks 28-40+ Guide

The third trimester brings physical challenges and birth preparation. Here's what to expect, which tests matter most, and how to recognise labour.

Duration
Week 28-40+
Full term
37-42 weeks
GBS testing
35-37 weeks (if offered)
Induction discussion
From 41 weeks

Common Symptoms

Signs of Labour

SignDescription
Regular, strengthening contractionsGetting closer together, longer, and more intense over time
ShowMucus plug (may be blood-tinged) coming away
Waters breakingGush or trickle of clear/pink fluid
BackachePersistent lower back pain, sometimes rhythmic

Group B Streptococcus (GBS)

GBS is a common bacteria that can be passed to the baby during birth, occasionally causing serious infection. Testing (usually a vaginal/rectal swab at 35-37 weeks) isn't routine everywhere but is recommended for higher-risk pregnancies. If positive, IV antibiotics during labour dramatically reduce transmission risk.
Go to Maternity Triage Immediately IfReduced fetal movements, vaginal bleeding, severe headache with visual disturbance, waters breaking before 37 weeks, regular painful contractions before 37 weeks, or if you have any concern at all — trust your instincts.
Braxton Hicks vs Real LabourBraxton Hicks contractions are irregular, don't increase in intensity, and often ease with movement or a warm bath. True labour contractions become progressively stronger, longer, and closer together, and don't ease with rest.
When should I go to hospital once labour starts?
Generally when contractions are regular, about 5 minutes apart, lasting 60 seconds, for at least an hour (the '5-1-1 rule') — though your midwife will give personalised guidance based on your pregnancy.
What happens if I go overdue?
Most units offer induction of labour discussions from 41 weeks, as the risk of complications rises gradually after 42 weeks. Membrane sweeps may be offered from 40-41 weeks to encourage natural labour.
Is swelling in pregnancy always normal?
Mild swelling in feet/ankles, especially by evening, is common and normal. However, sudden swelling of the face, hands, or a rapid increase can be a sign of pre-eclampsia and should be checked urgently.
Medical Disclaimer: This page is for general education only and does not replace professional medical advice. Always consult a qualified healthcare provider.