Ten Weeks

Week 10 marks a milestone for your baby-to-be. This first part of fetal development is all about organization. All your baby-to-be's cells have been directed to their places—brain tissue is growing rapidly, muscles are forming, fingers and toes are becoming defined. Your baby-to-be looks less like an embryo (or an alien) and more like the baby in miniature that he is. He's getting bigger, too.

This week your little one is about 1 1/4 inches long and weighs in at .04 ounce. He's about the size of a red grape.