Week 33 · 3rd trimester

Pregnancy Week 33: What to Expect

Baby's development, your body's changes, common symptoms, what to eat, and what to do this week.

Baby's size this week: Pineapple (~43 cm)

Baby's development at week 33

Baby's bones are hardening (except the skull, which stays flexible for delivery). Baby's immune system is developing — baby is receiving antibodies from you through the placenta. Baby's central nervous system matures. Baby can hear and distinguish many sounds. Baby's brain shows complex activity. Baby may be head-down by now.

What's happening in your body

Your uterus is about 5.5 inches above the belly button. Frequent urination (the bladder is being squeezed). Possible swollen feet. Sleeping flat impossible. Possible carpal tunnel. Possible Braxton Hicks. Pelvic pressure. Mild back pain. Skin on the belly stretched tight.

Common symptoms at week 33

Frequent urination. Possible swollen feet/ankles. Sleep difficult. Possible carpal tunnel. Possible Braxton Hicks. Strong fetal movements. Pelvic pressure. Mild back pain. Possible mild dizziness.

When to call your provider

Watery discharge or any sudden gush, painful regular contractions (every 5 minutes), bleeding, severe headache/vision changes — call provider.

How to feel better this week

Install the car seat — or schedule an inspection at your local fire station or a certified Child Passenger Safety Technician. Installation is more complicated than the manual suggests, and an inspection takes 20 minutes. Most fire stations do this free. Continue Kegels. Side sleeping. Walks. Hydrate. Apply lotion. Take breaks; rest when needed.

Nutrition focus for week 33

Continue iron, calcium, protein, fiber, healthy fats. Eat the rainbow. Add probiotics (yogurt, kefir, fermented vegetables) — they may help baby's microbiome development. Stay hydrated.

For your partner

Install or check the car seat together. Practice the buckle and strap until it feels easy. You will be exhausted after delivery; muscle memory helps.

This week's to-do

Install the car seat. Get it inspected if possible.

Is this normal?

Car seats expire after about 6-10 years (manufacturer-dependent). If yours is a hand-me-down, check the date stamp on the seat. Expired car seats can crack and fail in a crash.

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Medical disclaimer: This content is for general educational purposes only and is not a substitute for medical advice. Always talk to your healthcare provider about your specific pregnancy. If you have concerning symptoms, do not wait — call your provider or go to the emergency department.