27 WEEKS PREGNANT

The third trimester approaches as brain tissue grows rapidly

Baby this week: about 35.6 cm — head to heel · about 875 g

35.6 cm — about the size of an eggplant

Illustration enlarged for clarity — the amber marker shows true relative size

Your baby this week

  • Brain tissue is growing quickly, and brain activity is increasing
  • The fetus has regular sleep and wake cycles now
  • Hiccups are common and may be felt as small rhythmic jumps
  • The lungs, while still immature, are steadily developing toward being ready for air

Your body this week

  • This week typically marks the end of the second trimester
  • Rib discomfort can start as the uterus pushes upward

This week's tip: Shifting position or taking a few slow, deep breaths can sometimes ease rib discomfort caused by the growing uterus.

Want the bigger picture — organ development, nutrition, scans and warning signs for this stage? See month 6: Settling into the bump.

Sizes and milestones are typical ranges — every pregnancy runs on its own clock. Educational content; your prenatal care team's guidance always comes first.