Third trimester

Week 39: Full term

You’re 39 weeks pregnant — about 1 week to go. Your baby is roughly the size of a mini watermelon.

39 of 40 weeks

Size of

a mini watermelon

Length

50.7 cm

20.0 in · head to heel

Weight

3.29 kg

116.0 oz

Your baby this week

Your baby is full term and ready to meet you. They’re still building a layer of fat for temperature control, and the umbilical cord is passing along antibodies for immunity.

Your body & how you might feel

The waiting can feel endless. Keep an eye out for labour signs and stay in touch with your provider about movement and any changes.

Common symptoms at week 39

  • Lightning crotch
  • Diarrhoea
  • Contractions
  • Restlessness

This week’s tip: Keep tracking your baby’s movements — a noticeable change or decrease is always worth a prompt call to your provider.

A gentle reminder: This is an estimate, not medical advice. Dates and figures are general guidance — every pregnancy is different. Your healthcare provider’s assessment, especially from an early ultrasound, always takes priority. Always speak with your provider about your pregnancy.

Week 39 FAQs

How big is the baby at 39 weeks?

At 39 weeks pregnant, your baby is roughly the size of a mini watermelon, about 50.7 cm (20.0 in) long and around 3.29 kg. These are typical averages — every baby grows at its own pace.

How many months is 39 weeks pregnant?

39 weeks pregnant is about 9 months, in the third trimester, with about 1 week to go until your due date.

What are common symptoms at 39 weeks?

Common experiences around week 39 include lightning crotch, diarrhoea, contractions, restlessness. Symptoms vary widely — contact your provider if anything worries you.