31 WEEKS PREGNANT
Rapid brain development continues as the fetus processes information
Baby this week: about 41.3 cm — head to heel · about 1.5 kg
≈ 41.3 cm — about the size of a coconut
Illustration enlarged for clarity — the amber marker shows true relative size
Your baby this week
- The brain is developing at a rapid pace, forming new connections constantly
- The fetus can turn its head from side to side
- Many babies gain roughly half a pound a week from this point on
- The immune system is starting to develop, aided by antibodies passed from the parent
Your body this week
- Shortness of breath and heartburn are common as the uterus pushes against the diaphragm and stomach
- Some notice colostrum, an early form of breast milk, beginning to appear
This week's tip: Eating smaller meals more often and staying upright after eating can help ease heartburn.
Want the bigger picture — organ development, nutrition, scans and warning signs for this stage? See month 7: The world gets louder.
Sizes and milestones are typical ranges — every pregnancy runs on its own clock. Educational content; your prenatal care team's guidance always comes first.