🎃 Week 40

40 Weeks Pregnant: What to Expect This Week

Forty weeks pregnant — your due date. Only about 5% of babies arrive on their exact due date, but this week marks the completion of an extraordinary journey. Your baby is fully ready.

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Baby at Week 40: Size of a small pumpkin

📏 ~51.2cm long ⚖️ ~3.4kg 📅 Week 40 of 40

Baby's Development at 40 Weeks

Baby is fully developed in every way. The lungs are mature, the brain is making connections, the digestive system is primed. Baby has shed most of the vernix and lanugo. The placenta — which has supported an entirely new human being for nine months — is beginning to age and will be delivered shortly after your baby. At around 51cm and 3.4kg on average, your baby is perfectly formed and ready to meet you.

Your Body at 40 Weeks Pregnant

Anxiety, impatience, and exhaustion are the dominant experiences this week. Pre-labour activity (show, irregular contractions, loose stools, restlessness) may be intense. Mentally, many people oscillate between wanting the baby out immediately and a profound awareness that these are the last moments of life before everything changes. Both are entirely valid.

Tips for Week 40

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On Hello, baby: Have Hello, baby open and ready on both phones — this is the week everything could happen, and you'll want to capture every moment.
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Frequently Asked Questions

What happens if I go past my due date?

Going past 40 weeks is very common — about 50% of first-time parents do. Most providers offer a membrane sweep from week 39–40 and discuss induction if you reach 41–42 weeks, as the risk of stillbirth begins to rise after 42 weeks. Additional monitoring (non-stress tests, biophysical profiles, fluid checks) is offered from around 41 weeks.

What is a membrane sweep?

A membrane sweep (or stretch and sweep) is a procedure where a midwife or doctor inserts a finger through the cervix and sweeps it around to separate the membranes from the cervix. This releases prostaglandins that may trigger labour. It's offered from around 39 weeks in many countries and has reasonable evidence for reducing the need for formal induction. It can cause cramping and spotting.

Stay connected as you wait

Hello, baby keeps both partners in the loop in real time — perfect for these final, exciting, anxious days.

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