Second trimester
Week 17 of Pregnancy
🥔
About the size of a turnip
5.1 in · 13.0 cm · 4.9 oz · 140 g (crown to rump)
Your baby this week
- Brown fat begins forming — it will help regulate body temperature after birth.
- Bones are hardening as cartilage turns to bone (ossification).
- The umbilical cord — the baby's lifeline — grows thicker and stronger.
What you may be feeling
- Growing appetite
- Brief, sharp round ligament pains low on the sides
- Occasional dizziness
Gentle tips for this week
- Second-trimester calorie needs rise only modestly — roughly an extra snack a day over your pre-pregnancy intake.
- Change positions slowly to avoid quick blood-pressure drops.
Common question for week 17
How much more should I eat during pregnancy?
Less than most people expect: no extra calories in the first trimester, roughly 340 more per day in the second and about 450 more in the third, compared with pre-pregnancy needs.
Every pregnancy is different. Sizes are averages, symptoms vary widely, and none of this replaces the guidance of your own provider.