Articles
Fetal development: The second trimester
Week 13: Urine forms
Week 14: Baby's sex becoming apparent
Week 15: Baby's scalp pattern develops
Week 16: Baby's eyes move
Week 17: Baby's toenails develop
Week 18: Baby begins to hear
Week 19: Baby develops protective coating
Week 21: Baby can suck his or her thumb
Week 22: Baby's hair becomes visible
Week 24: Baby's skin is wrinkled
Week 26: Baby's lungs develop
Week 27: 2nd trimester ends
Content
Week 13: Bones start to harden
Week 14: Red blood cells form
Week 15: Bone development continues
Week 16: Eyes move
Week 17: Toenails develop
Week 18: Hearing develops
Week 19: A protective coating forms
Week 20: The halfway point
Week 21: Baby can suck a thumb
Week 22: Hair becomes visible
Week 23: Fingerprints and footprints form
Week 24: Skin is wrinkled
Week 25: Baby responds to your voice
Week 26: Eyebrows and eyelashes form
Week 27: Second trimester ends
Week 14: Baby's sex becoming apparent
Week 15: Baby's scalp pattern develops
Week 16: Baby's eyes move
Week 17: Baby's toenails develop
Week 18: Baby begins to hear
Week 19: Baby develops protective coating
Week 21: Baby can suck his or her thumb
Week 22: Baby's hair becomes visible
Week 24: Baby's skin is wrinkled
Week 26: Baby's lungs develop
Week 27: 2nd trimester ends
Content
Week 13: Bones start to harden
Week 14: Red blood cells form
Week 15: Bone development continues
Week 16: Eyes move
Week 17: Toenails develop
Week 18: Hearing develops
Week 19: A protective coating forms
Week 20: The halfway point
Week 21: Baby can suck a thumb
Week 22: Hair becomes visible
Week 23: Fingerprints and footprints form
Week 24: Skin is wrinkled
Week 25: Baby responds to your voice
Week 26: Eyebrows and eyelashes form
Week 27: Second trimester ends
Week 23: Fingerprints and footprints form
Twenty-three weeks into your pregnancy, or 21 weeks after conception, your baby starts to have rapid eye movements. Ridges also form in the palms of the hands and soles of the feet that will create the foundation for fingerprints and footprints.
The lungs are starting to make a substance called surfactant. It allows the air sacs in the lungs to inflate and keeps the lungs from collapsing and sticking together when they deflate.
If born preterm, some babies this far along in pregnancy may be able to survive outside the uterus.
