Your baby is now around 1.5 inches long. His head: body ratio is about 1:1. A stage of rapid weight gain now starts. From week 11 until week 20 of pregnancy — your baby will increase his or her weight thirty fold and will about triple in length. To accommodate this growth, blood vessels in your placenta are growing larger/more numerous to keep up the supply of nutrients. His fingers/toes have separated, and his hands will soon open/close into fists. Tooth buds begin to appear under his gums, and his bones begin to harden. His or her ears are moving up and to the side of the head this week, and his reproductive organs are developing. The baby’s skin is still transparent.