Your baby is the size of a coffee bean. His brain is developing rapidly and the cranial nerves have appeared. His face takes shape. Your baby’s heart now has two auricles, and the ultrasound can detect his heartbeat. The esophagus and trachea are now two separate tubes and lungs are being formed on each side of these structures.

This week

Baby measures about 8 mm (from head to heel)
Baby weighs about 0.5 grams