Week 39: Full Term
The baby is full term — ideal delivery window opens now
Week 39 is considered full term — the optimal time for delivery. The baby's lungs, brain, and liver are fully mature. If your OB has discussed elective induction or scheduled C-section, this is typically the earliest they'd do it. Otherwise, you're watching for natural labor. The phone is always charged. The bag is by the door.
What's happening this week
The baby weighs about 7.2 pounds and is around 20 inches long. The immune system has received its final batch of antibodies from the mother. The chest is protruding as the baby practices breathing. The baby's position is locked in — most are head-down with the chin tucked. She may notice increased mucus discharge (the mucus plug loosening) and irregular contractions that come and go.
Your checklist
0 of 4 completeEarly labor: contractions 10–20 minutes apart, mild to moderate intensity. This can last hours or even a day. You don't need to rush to the hospital yet. Active labor: contractions 5 minutes apart or closer, lasting 1 minute, for at least 1 hour (5-1-1). This is when you go.
Whoever is watching pets, kids, or coming to help postpartum should know 'it's almost time.' A group text or family chat keeps everyone informed without requiring individual updates during labor.
Seriously. Sleep when you can. Eat well. Stay hydrated. Labor is a marathon, and the first days with a newborn are sleep-deprivation boot camp. You need reserves. Both of you.
After the baby is born, you'll need to: apply for the birth certificate and Social Security number (hospital handles paperwork), add baby to insurance within 30 days, schedule the first pediatrician appointment (3–5 days after discharge), and notify family/friends. Know these steps now.
Recommended products
Newborn Diapers — Pampers Swaddlers
The most popular newborn diaper for a reason. Ultra-soft, wetness indicator strip, umbilical cord notch for newborns. Grab a box of Size 1 and a small pack of Newborn size — most babies outgrow Newborn within the first week or two.
Week 39 is clinically defined as full term — the gestational age at which all major organ systems have reached maturity and delivery outcomes are optimal. ACOG considers 39 weeks the earliest appropriate time for elective induction or scheduled C-section in the absence of medical indication.
For dads, the full-term milestone brings a mix of relief and anticipation. The baby is safe to arrive at any point. The focus now is on recognizing true labor, executing the hospital plan, and supporting her through what may be the most physically demanding experience of her life. Review your birth plan one final time, confirm your OB's after-hours contact process, and make sure the car has gas and the hospital bag is accessible.
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