Week 39 · 3rd trimester

Pregnancy Week 39: What to Expect

Baby's development, your body's changes, common symptoms, what to eat, and what to do this week.

Baby's size this week: Watermelon or pumpkin (~50 cm; about 7 lb)

Baby's development at week 39

Baby is essentially full-term. Subcutaneous fat softens the skin. Baby has fully mature lungs. Baby has a strong grasp reflex. Baby's brain continues developing. Baby is "ready" to be born.

What's happening in your body

Your uterus is at peak height. Heavy pelvic pressure. Possible sciatica from baby's head pressing on nerves. Sleep is very short. Strong Braxton Hicks. Possible early labor signs — irregular contractions becoming more regular, lower back pain, increased pelvic pressure.

Common symptoms at week 39

Heavy pelvic pressure. Possible sciatica. Sleep very short. Possible Braxton Hicks intensifying. Mood swings. Anticipation. Possible early labor signs (irregular contractions, pelvic pressure). Possible loss of mucus plug.

When to call your provider

Water breaking — sudden gush or persistent trickle — call provider. Note the time. Regular painful contractions (every 5 minutes for an hour, intensifying). Bleeding. Severe headache/vision changes. Decreased fetal movement.

How to feel better this week

Walk daily — gentle exercise can help labor start naturally. Practice deep breathing. Stay hydrated. Eat balanced meals. Try dates. Rest when you can. Have the hospital bag by the door. Have a plan for who calls who when labor starts.

Nutrition focus for week 39

Continue all nutrients. Hydration is critical. Eat dates. Iron, calcium, protein.

For your partner

Be on call. Have the bag in the car. Confirm the plan for older kids/pets. Make sure your phone is charged.

This week's to-do

Walk daily. Be ready for labor any moment.

Is this normal?

A "pop" or sudden gush followed by trickling water is your water breaking. It can also be slow and gradual. Note the time, color (should be clear or pale yellow; green or brown means meconium and warrants immediate provider call), and call.

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Medical disclaimer: This content is for general educational purposes only and is not a substitute for medical advice. Always talk to your healthcare provider about your specific pregnancy. If you have concerning symptoms, do not wait — call your provider or go to the emergency department.

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