Third Trimester

Week 28

Baby is the size of a eggplant

• Third trimester begins!
• Eyes can focus; REM sleep regular

Week 29

Baby is the size of a butternut squash

• Muscle tone developing; kicks stronger
• Brain controlling breathing and body temperature

Week 30

Baby is the size of a zucchini

• Hands and feet fully developed; fingernails growing
• Vision sharpens; tracks light

Week 31

Baby is the size of a coconut

• Most babies turn head-down (cephalic) by 31-32 weeks
• Brain connections multiplying rapidly

Week 32

Baby is the size of a honeydew

• Skin smooth as fat fills out wrinkles
• Practice breathing strong; lungs more mature

Week 33

Baby is the size of a pineapple

• Skull bones flexible for birth passage
• Immune system developing; receiving antibodies from mom

Week 34

Baby is the size of a cantaloupe (small)

• Vernix thickens (protective coating)
• Lungs nearly mature

Week 35

Baby is the size of a honeydew (large)

• Brain and lungs nearly fully developed
• Most space taken — kicks feel more like rolls and stretches

Week 36

Baby is the size of a romaine lettuce

• Lungs fully mature — ready for first breath
• Dropping lower into pelvis (engagement)

Week 37

Baby is the size of a bunch of kale

• Full term! Baby is ready for life outside
• Practicing breathing, sucking, swallowing

Week 38

Baby is the size of a leek

• Meconium (first stool) accumulating in intestines
• Brain and lungs fully mature

Week 39

Baby is the size of a watermelon (small)

• Full term — baby ready for life outside
• Placenta still nourishing; antibody transfer peaks

Week 40

Baby is the size of a watermelon

• Due date week! Baby fully ready
• Vernix mostly gone; skin smooth

Week 41

Baby is the size of a jackfruit

• Past due date — but still within normal range
• Placenta still functioning; amniotic fluid may decrease

Week 42

Baby is the size of a jackfruit

• Post-term — induction strongly recommended
• Placenta aging; amniotic fluid may be low