The baby is between 4 and 5 inches long; he weighs 85 grams. The skeletal and nervous system have enough connections to signal movements of the limbs. His facial muscles are now well enough developed to have a variety of expressions. Your baby’s skeletal system develops as more calcium is deposited. For girls, eggs are forming in her ovaries this week. Your baby’s eyes are sensitive to light. Your baby might be having frequent hiccups. They develop before your baby practices lung movements (to prepare with breathing). His backbone and tiny muscles are developing. His skin is still translucent. The bones in his ears have formed, making it likely that he can hear you.