Fine hair (lanugo) starts covering the fetus. The neck becomes defined. You may start feeling flutters of movement.
Week 25 - Brain Growth Spurt
Week 10 - Fingernails Form
Week 34 - Immune System Develops
Fertility Test Basics: Your Guide to Tracking Pregnancy
Pregnancy Intimacy Guide
Cycle Phase Overview
Week 6 - Limb Buds Appear
Week 14 - Bones Harden