MONTH 9 · WEEKS 36–40

The waiting month

The final stretch is largely about fine-tuning what's already built. Lungs finish maturing and are typically ready for that first breath by around week 37, which is why a full-term due date has a range rather than a single fixed day. Fat continues building under the skin, smoothing things out, while the baby drops lower into the pelvis in preparation for labor.

Baby this month: about 50 cm — crown to heel, close to the length of a small watermelon · 3–3.5 kg

50 cm — about the size of a small watermelon

Illustration enlarged for clarity — the amber marker shows true relative size · head-down, ready position

What's developing right now

Lungs

Finish maturing around week 37, generally ready to support breathing outside the womb from full term onward.

Brain

Continues rapid growth that will keep going well after birth.

Body fat

Rounds out the baby's appearance and helps regulate temperature after delivery.

Digestive system

Fully formed and ready to begin processing milk shortly after birth.

What your body is doing

  • The baby typically drops lower into the pelvis, a shift sometimes called 'lightening.'
  • Contractions may become more frequent as the body prepares for labor.
  • Pelvic pressure and frequent urination often increase again.
  • Nesting energy or, alternatively, exhaustion can both be common in these final weeks.

Eating for this month

Nutrient needs stay similar to month eight, with a continued focus on steady energy, iron, and calcium as the body prepares for labor and, later, feeding. Staying hydrated and eating light, frequent meals can help when there's little room left in the abdomen. This is a good month to keep meals simple and manageable rather than ambitious.

Datesa fruit some people include in late pregnancy for their natural sugars and fiber, alongside standard medical care
Bananasa convenient source of potassium and quick energy for the unpredictable pace of these final weeks
Berries (mixed)a source of antioxidants and vitamin C in a light, easy-to-eat form
Pearsprovide fiber that can help with the constipation common in the final weeks of pregnancy

Checkups commonly done this month

  • Weekly prenatal visits to check the baby's position, heart rate, and the parent's blood pressure — schedules vary by country and doctor
  • A group B strep swab, commonly done around weeks 36–37
  • A cervical check in the final weeks, if relevant to the birth plan
  • Non-stress tests or growth scans if the pregnancy goes past the due date

Contact your doctor promptly if…

Contractions that become regular, strong, and closer together

Leaking fluid or a sudden gush, which may signal the waters breaking

A noticeable decrease in fetal movement

Severe headache, vision changes, or sudden swelling suggesting preeclampsia

Questions people ask

What if the due date passes without labor starting?

It's common — only a minority of babies arrive exactly on their due date, and many pregnancies continue a week or so beyond it. Doctors typically monitor more closely past the due date and may discuss options for encouraging labor if it stretches significantly beyond 40 weeks.

How will I know labor has actually started?

True labor contractions become regular, get closer together over time, and grow stronger despite rest or position changes, unlike the irregular Braxton Hicks tightenings from earlier months. Other signs can include the waters breaking or a bloody show. A doctor or midwife can help clarify what's being felt if it's unclear.

Sizes and milestones are typical ranges — every pregnancy runs on its own clock. Educational content; your prenatal care team's guidance always comes first.