29 Weeks Pregnant: Baby’s Brain Is Developing Rapidly
Medically reviewed by
Maureen Kelly, RN — 20+ years in L&D, postpartum, NICU, and women’s health.
Reviewed against ACOG, AAP, and Mayo Clinic guidance. Meet Maureen →
Medical Disclaimer: This article is for informational purposes only. Always consult your healthcare provider.
At 29 weeks, your baby is about the size of a butternut squash—roughly 15.5 inches long and weighing about 2.5 pounds. Your baby’s brain is developing at an extraordinary rate, and they’re gaining weight rapidly to prepare for life outside the womb. You’re in the home stretch now, with about 11 weeks until your due date.
Baby Development at 29 Weeks
Your baby measures about 15.5 inches and weighs approximately 2.5 pounds. The brain is growing rapidly, with the surface becoming more wrinkled to accommodate billions of neurons. Your baby’s muscles and lungs continue maturing.
Your baby’s bones are fully developed but still soft and flexible (they need to be for delivery). Fat accumulation accelerates, making your baby chubbier each week. Your baby can regulate their own body temperature better now, though not yet as well as they will at full term.
Your Body This Week
Your uterus is about 3-4 inches above your belly button. Weight gain is typically 19-25 pounds. You may find it harder to take deep breaths, sleep comfortably, or move around easily. Your belly may feel tight and stretched.
Frequent urination is intensifying as your baby grows and puts more pressure on your bladder. Hemorrhoids, varicose veins, and swelling may worsen.
Common Symptoms at 29 Weeks
Difficulty sleeping: Between bathroom trips, heartburn, back pain, and difficulty finding comfortable positions, sleep becomes challenging. See our sleep guide.
Heartburn: Worsening as your uterus compresses your stomach. Small meals, avoiding spicy foods, and not lying down after eating help.
Fatigue: Third-trimester fatigue is real. Your body is working hard to support your growing baby. Rest when you can.
Swelling: Mild swelling in feet, ankles, and hands is normal. Sudden or severe swelling needs medical attention.
What to Do This Week
Continue kick counts daily. Report any significant decrease in movement to your provider immediately.
Finalize your birth plan. Discuss preferences with your provider and partner. See our template.
Start preparing for breastfeeding. Take a breastfeeding class or read about it. Our breastfeeding guide covers what to expect.
Consider your postpartum plan. Who will help after delivery? What meals can you prep? See our meal prep guide.
Nutrition Spotlight: Protein Power
Your baby is gaining weight rapidly and needs protein for growth. Aim for 70-100 grams daily from lean meats, fish, eggs, dairy, beans, nuts, and tofu. Protein also helps you maintain muscle mass and energy. Visit our nutrition guide.
When to Call Your Doctor
- Fewer than 10 movements in 2 hours
- Regular contractions before 37 weeks
- Vaginal bleeding or fluid leaking
- Severe headaches or vision changes
- Sudden severe swelling
See our when to call your doctor guide.
Frequently Asked Questions
How much weight will my baby gain from now to delivery?
Your baby will approximately triple in weight, going from about 2.5 pounds to 6-8+ pounds by delivery. Most weight gain occurs in the final 8-10 weeks.
When should I start preparing for breastfeeding?
Now is a great time. Take a breastfeeding class, read about common challenges, and discuss your plans with your provider. Having support lined up before delivery makes a big difference.
Is it normal to feel really tired in the third trimester?
Very normal. Your body is working hard, you may be sleeping poorly, and the physical demands of carrying a growing baby are significant. Rest when possible and prioritize sleep.
Get weekly pregnancy updates
Key takeaways for the third trimester
- Prenatal visits move to every 2 weeks at week 28, then weekly from week 36.
- Group B strep (GBS) screening is performed between weeks 36 and 37.
- Kick counts become important — track 10 movements within 2 hours during baby’s active period.
- Heartburn, swelling, back pain, frequent urination, and sleep disruption are all common and intensify in the third trimester.
- “Lightening” (baby drops into the pelvis) often happens 2–4 weeks before labor in first pregnancies; sometimes only at the start of labor in subsequent pregnancies.
When to call your provider
Call your OB-GYN, midwife, or labor and delivery unit right away if you experience:
- Heavy vaginal bleeding (more than light spotting)
- Severe abdominal or pelvic pain
- A severe headache that doesn’t respond to acetaminophen
- Sudden facial, hand, or leg swelling
- Vision changes (spots, blurring, light sensitivity)
- Decreased fetal movement after 28 weeks (fewer than 10 movements in 2 hours during baby’s active period)
- Signs of preterm labor: regular contractions, pelvic pressure, low back pain, fluid leaking
- Fever over 100.4°F (38°C)
When in doubt, call. Your provider would always rather hear from you about a non-issue than miss something important.
Frequently asked questions about week 29
How big is the baby at 29 weeks pregnant?
At 29 weeks, your baby is roughly the size of a butternut squash (~15.2 inches, 2.5 lb). Size estimates vary from baby to baby and are based on standardized growth charts (ACOG, NICHD).
What symptoms are common at 29 weeks pregnant?
Common third-trimester symptoms include heartburn, swelling in feet and ankles, low back pain, frequent urination, Braxton Hicks contractions, sleep disruption, and a heightened sense of fatigue. The body is preparing for labor.
What prenatal appointments happen around 29 weeks?
Visits move to every 2 weeks at week 28. Tdap vaccination is recommended between weeks 27 and 36.
When should I worry at 29 weeks pregnant?
Fewer than 10 fetal movements in a 2-hour period (during baby’s active time), regular contractions, vaginal bleeding, leaking fluid (possible ruptured membranes), severe headache, sudden swelling, vision changes, or any symptom that just feels wrong warrants immediate evaluation.
Is what I’m feeling at 29 weeks normal?
Most of the symptoms experienced at 29 weeks are part of typical pregnancy and reflect your body’s adjustments. If anything feels alarming, severe, or unusual for you, contact your provider — trust your instincts.
Sources
- American College of Obstetricians and Gynecologists (ACOG). Your Pregnancy and Childbirth: Month to Month (current edition). acog.org
- American Academy of Pediatrics. Caring for Your Baby and Young Child (current edition).
- Mayo Clinic. Pregnancy week by week. mayoclinic.org
- National Institute of Child Health and Human Development (NICHD). Pregnancy and Pregnancy Loss research and guidance.