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first month
As the fertilized egg grows, a water-tight sac forms around it, gradually filling with fluid. This is called the amniotic sac, and it helps cushion the growing embryo. During this time, the placenta also develops -
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second month
Tiny buds that eventually grow into arms and legs are forming. Fingers, toes and eyes are also forming. The brain, spinal cord and other neural tissue of the central nervous system is well formed now. Also the digestive tract and sensory organs will begin to develop. -
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third month
Fingernails and toenails are beginning to develop and the external ears are formed. The beginnings of teeth are forming under the gums. The reproductive organs also develop, but sex is still difficult to distinguish on ultrasound, by the end of the third month, the fetus is fully formed. -
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fourth month
By the end of the fourth month, the fetus is about 6 inches long and weighs about 4 ounces. At this stage, you may begin to feel the fetus moving around. The fetus is developing muscles and exercising them. This first movement is called quickening and can feel like a flutter -
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fifth month
Hair is beginning to grow on your baby's head, and lanugo, a soft fine hair, covers their shoulders, back, and temples. This hair protects your baby and is usually shed at the end of the baby's first week of life -
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sixth month
By the end of the sixth month, the fetus is about 12 inches long and weighs about 2 pounds. The fetus continues to mature and develop reserves of body fat. At this point, hearing is fully developed. The fetus changes position frequently and responds to stimuli, including sound, pain and light -
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seventh month
At the end of the seventh month of pregnancy, fat begins to be deposited on your baby. Your baby is about 14 inches long and weighs from about two to four pound. Your baby's hearing is fully developed and they change position frequently -
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eighth month
Your baby, who is now about 18 inches long and weighs as much as about five pounds, will continue to mature and develop body fat reserves. You may notice that your baby is kicking more. Baby's brain is developing rapidly at this time, and they can see and hear even more -
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ninth month
In addition to rocking an impressive growth spurt, your baby experiences significant development during the ninth month of pregnancy. For instance, baby's lungs are maturing to breathe outside of the womb, their reflexes are more coordinated, and they can blink, turn their head, and grasp nd at this time this is when birth is occuring