Week 34: Development of the Immune System
The thirty-fourth week is a time of active development of your baby's immune system.
Baby size: Cantaloupe (140-145 mm)
Baby development
Protective layer and strong bones
Your baby is becoming more and more like a full-term infant. The protective vernix (vernix caseosa) on his skin is getting thicker, and the nails fully cover the nail beds.
What’s happening this week:
- Lungs: They are almost mature.
- Bones: They continue to harden, except for the skull bones.
- Central nervous system: It continues to develop actively.
- Position: Most babies are already in a head‑down (cephalic) presentation.
Your fetus weighs about 2.1 kg, and its length is over 45 centimeters.
Changes for mom
Blurry vision and pelvic pain
Your body continues to prepare for labor, which can trigger new symptoms and intensify existing ones.
What you may notice:
- Blurry vision: Hormonal changes and fluid retention can affect corneal thickness. This will pass after delivery.
- Pelvic pain (symphysis pubis dysfunction): Relaxation of the pubic symphysis can cause significant discomfort when walking.
- Fatigue: The need for rest becomes greater.
- Increased swelling: It’s important to monitor them and inform your doctor of any sudden changes.
It’s important to distinguish normal symptoms from concerning ones. Learn more about possible complications in the article "Complications and Risks During Pregnancy".
Overview
Week 34: Baby is training, and you are preparing
At the thirty-fourth week, your baby is almost fully ready for birth. His lungs continue to mature, and the body becomes increasingly plump due to fat accumulation. He already responds well to external stimuli.
He is now the size of a large melon. If it’s a boy, this week his testicles descend from the abdominal cavity into the scrotum. This is an important stage in his development.
For you, this is a time when fatigue can reach its peak. You may notice that your vision has become a bit blurry — this is related to fluid retention and is a temporary phenomenon. It’s important to rest a lot and avoid overexertion.
Your baby is almost ready to meet you. Every day in the womb now benefits his lungs and immune system. Enjoy these final weeks of "shared" life.
You are on the home stretch. To know what to prepare for at this stage, read our detailed overview "Third Trimester: What You Need to Know".
Tips for mom
Preparing for labor and the postpartum period
Now is the time to focus on final preparations and planning the first weeks after the baby’s birth.
What to do:
- Discuss any vision changes with your doctor. It’s usually normal, but it’s worth confirming.
- Learn perineal massage techniques. This can help reduce the risk of tears during labor.
- Create a plan for the postpartum period. Who will help you? Who will prepare meals?
- Gather contact information for a breastfeeding consultant. Save the phone number to have support right after delivery.
Knowledge is your superpower. Start preparing for feeding in advance by reading the article "Basics of Breastfeeding".
Tips for partner
The main person for calm and organization
Your confidence and practical help are now key to your partner’s peace of mind.
Your contribution to the joint effort:
- Be her eyes. If her vision has slightly worsened, help her with household tasks.
- Become the route expert. Drive to the birthing center a few times so you know the way perfectly.
- Assist with organizing postpartum support. Take on the calls to relatives and friends.
- Prepare an "emergency bag" for yourself. Snacks, water, change of clothes, power bank — be ready.
Your readiness for the most important day is the guarantee of her calm. Re‑read the article about signs of labor onset.
Checklist
Your action plan for week 34
The finish line is getting closer.
- ✅ Discuss perineal massage technique with your doctor.
- 🤱 Save the contact details of the breastfeeding consultant.
- 🤝 Create a support plan for the first weeks after birth.
- 👜 Check that all bags for the hospital are packed.
- 🚗 Test the route to the birthing center.
- 📚 Refresh your knowledge about the “fourth trimester” by reading the article "Fourth Trimester: Needs of the Newborn".