All Pregnancy Weeks
Third TrimesterWeek 40 of 40

Pregnancy Week 40: The Arrival

Updated

Your baby this week
About the size of a small pumpkin
~20.2 in · ~7.5 lb

Medical Disclaimer: Content is for informational purposes only and does not replace professional medical advice. Always consult your healthcare provider.

How your baby is growing this week

About the size of a small pumpkin — roughly 20.2 inches, 7.5 lbs. The skull bones are soft and unfused, so they can overlap slightly to fit through the birth canal. Vernix and lanugo are nearly gone. Everything is finished — baby is just waiting for the signal that starts labor.

What your partner is going through

Labor could start any time. Watch for regular contractions that build — the 5-1-1 rule is every 5 minutes, lasting 1 minute, for 1 hour — plus the bloody-show mucus plug or water breaking. Early labor can run hours; there is usually time to breathe and call the OB.

What to focus on this week, dad

  • 01Go Time: execute the hospital route you practiced
  • 02Support mom — be her calm, her advocate, her voice when she can't speak
+1 more focus item in the full briefing for week 40 — Start free

Connect with your partner

One dad's rule for the delivery room: your only jobs are to stay calm, keep the ice chips coming, and be her voice with the staff. Do not stare at the monitors — watch her. If panic hits, step into the hall for 30 seconds, then come back steady.

Source: ACOG

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