42 Weeks Pregnant

Baby’s Development

Your baby is now about 51.7 centimeters long, roughly the size of a jackfruit, and weighs around 3,600 grams (about 7.9 pounds) [1]. You are now officially post-term, and induction is strongly recommended at this point. The placenta is aging and becoming less efficient, and the amniotic fluid levels may be running low. Your baby’s body fat now makes up about 15 to 16 percent of their weight, and the skin remains smooth and plump. The brain and lungs are fully mature, and most babies are settled in the head-down (cephalic) position. The survival rate remains over 99 percent [2].

Body Changes

Your uterus now measures about 42 centimeters in fundal height, and a total weight gain of 30 to 40 pounds by this point is typical. Your bump is large and has likely “dropped” as your baby settles lower into your pelvis. You may notice stretch marks, the linea nigra down your belly, melasma (the “pregnancy mask”), more visible veins, and varicose veins. Your breasts have likely grown two or more cup sizes, and some colostrum may be leaking as your body prepares to feed your baby. Swelling in your feet and ankles is common. Your cervix is likely effacing and may be dilating 1 to 4 centimeters [2].

Tips for Week 42

• Make an induction plan with your provider — ACOG strongly recommends induction at 42 weeks. Methods may include a membrane sweep, cervical ripening (with medications like Cervidil or Cytotec), Pitocin, or breaking your water. Ask your provider to walk you through the risks and benefits of each option.
• Expect a non-stress test (NST) — this painless test monitors your baby’s heart rate for 20 to 40 minutes and is typically done twice a week. A reassuring result means your baby is doing well.
• Ask about a biophysical profile (BPP) — this is an ultrasound that checks amniotic fluid, movement, muscle tone, and breathing, scored from 0 to 10. A score of 8 to 10 is considered reassuring.
• Keep counting your baby’s kicks — aim for at least 10 movements within a 2-hour window each day. If you count fewer than 10, call your provider right away.

Things To Do (Checklist)

• Induction scheduled (42 wk strongly recommended)
• NST 2x/week
• BPP if indicated
• Continue kick counting (10 in 2 hrs daily)
• Hospital bag ready, route mapped

Frequently Asked Questions

Q: I’m 42 weeks. Will induction work? A: Yes, usually. Cervical ripening medications like Cervidil or Cytotec help soften the cervix, and Pitocin helps start contractions. About 75 percent of induced labors end in a vaginal delivery. The C-section rate is slightly higher than with spontaneous labor, but most inductions succeed [1].

Q: What if the induction doesn’t work? A: There are options: your provider may let you rest and try again, or recommend a C-section. Most inductions do work within 24 to 48 hours. Talk through the possibilities with your provider ahead of time so you feel prepared [1].

Q: Is being post-term dangerous for the baby? A: There is a slightly higher risk of stillbirth (though still rare), macrosomia (a larger baby), meconium aspiration, and placental insufficiency. That’s exactly why induction is recommended at 41 to 42 weeks — it helps reduce these risks [1].

Sources

1. ACOG — How Your Fetus Grows During Pregnancy
2. Mayo Clinic — 42 Weeks Pregnant
3. What to Expect When You’re Expecting — Heidi Murkoff (Chapters 21-22: Labor & Delivery)

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Welcome to the World

Congratulations to you both. You’ve made it through 42 weeks of pregnancy. The journey ahead — postpartum recovery, newborn care, sleep deprivation, and the depths of love you haven’t yet imagined — is just beginning. Trust the process, lean on each other, and reach out for help. You don’t have to do it alone.

This is a milestone, not a destination. The adventure continues.