Third trimester · Week 33 of 40
33 weeks pregnant: the size of a pineapple
The immune system is developing, receiving antibodies from you.
Reviewed against ACOG, NHS and WHO guidance · Updated November 2026
Typical size
About 44 cm · 1.9 kg
83% of the way to your due date
Your baby this week
The immune system is developing, receiving antibodies from you.
Your body this week
Swelling, back pain and difficulty sleeping are common.
Tip for week 33
Know the signs of pre-eclampsia: severe headache, vision changes, sudden swelling.
Carry this guide in your pocket
Mamivaa is a free pregnancy app with a week-by-week tracker, vitamin and water reminders, a food scanner and a baby checklist.
Start freeThis guide offers general information and does not replace advice from your doctor or midwife. If something feels wrong, contact your provider or emergency services.