Fetal Development: Your Baby's Growth During the First Trimester

From fertilized egg to garlic bulb-sized baby, your little one quickly goes through some amazing changes during her early weeks in your womb. She starts to take shape during week 5, transforming from an egg into an embryo. Her umbilical cord forms, which connects her to your blood supply.

She's big enough to measure by week 6. But big is relative. She's just an eighth of an inch long. Her heart and lungs are growing too.

Next week, she's the shape of a tiny tadpole and roughly the size of a pomegranate seed. Teeny limb buds are forming. Eventually, they'll become her arms and legs. Her eyes, mouth, and stomach are starting to take shape too.

Your little one is about as big as a coffee bean by week 8. She can move around and swim now. Her tiny webbed fingers and toes are growing. Plus, her major organs have almost totally formed.

Next week, she's the size of a peanut. Her little eyelids are growing in. And her tiny nose appears too. Her skeleton also starts taking shape, although the bones are soft.

Your baby may be 1 inch big by week 10. That makes her about the size of a green olive. Her fingers and toes are becoming distinct, and her arms bend at the elbows.

During week 11, your little one might double in size to 2 inches. She's the size of a strawberry, and her teeth, intestines, and genitals are forming. By the end of your first trimester, your baby is almost as big as a 2 and 1/2-inch bulb of garlic. Her profile, complete with tiny nose and chin, have grown in too. She's come a long way this first trimester, and she's got a lot of growing left to do.