17 WEEKS PREGNANT
Fingerprints are fully formed
Baby this week: about 13 cm — crown to rump · about 140 g
≈ 13 cm — about the size of a pear
Illustration enlarged for clarity — the amber marker shows true relative size
Your baby this week
- Unique fingerprints and toe prints are now fully formed
- A layer of protective fat is just beginning to develop under the skin
- The umbilical cord is growing thicker and stronger to support the fetus
- Sweat glands are starting to develop
Your body this week
- Lower back aches can start as posture shifts to accommodate the growing belly
- Some notice a stronger appetite along with specific food cravings or aversions
This week's tip: Sleeping on your side with a pillow between your knees can ease lower back and hip discomfort.
Want the bigger picture — organ development, nutrition, scans and warning signs for this stage? See month 4: Finding out who's in there.
Sizes and milestones are typical ranges — every pregnancy runs on its own clock. Educational content; your prenatal care team's guidance always comes first.