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Conception
When the sperm and egg meet. -
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First Trimester
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1 Weeks. Fertilization
The sperm and egg unite in one of your fallopian tubes to form a one-celled entity called a zygote. -
Week 2: Implantation
The inner group of cells will become the embryo. The outer group will become the cells that nourish and protect it. On contact, it will burrow into the uterine wall for nourishment. This process is called implantation. -
Week 3: The embryonic period begins
The fifth week of pregnancy, or the third week after conception, marks the beginning of the embryonic period. This is when the baby's brain, spinal cord, heart and other organs begin to form. -
Week 4: The neural tube closes
Growth is rapid this week. Just four weeks after conception, the neural tube along your baby's back is closing and your baby's heart is pumping blood.
Basic facial features will begin to appear, including passageways that will make up the inner ear and arches that will contribute to the jaw. Your baby's body begins to take on a C-shaped curvature. Small buds will soon become arms and legs. -
Week 5: Baby's head develops
Seven weeks into your pregnancy, or five weeks after conception, your baby's brain and face are rapidly developing. Tiny nostrils become visible, and the eye lenses begin to form. The arm buds that sprouted last week now take on the shape of paddles. -
Week 6: Baby's eyes are visible
Eight weeks into your pregnancy, or six weeks after conception, your baby's arms and legs are growing longer, and fingers have begun to form. The shell-shaped parts of your baby's ears also are forming, and your baby's eyes are visible. The upper lip and nose have formed. The trunk of your baby's body is beginning to straighten. -
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Second Trimester
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12 Weeks: Baby's sex becomes apparent
Fourteen weeks into your pregnancy, or 12 weeks after conception, your baby's arms have almost reached the final relative lengths they'll be at birth and your baby's neck has become more defined. Red blood cells are forming in your baby's spleen.
Your baby's sex will become apparent this week or in the coming weeks. For girls, ovarian follicles begin forming. For boys, the prostate appears.
By now your baby might be almost 3 1/2 inches (90 millimeters) long from crown to rump and weigh about 1 1 -
14 Weeks: Baby can make sucking motions
Sixteen weeks into your pregnancy, or 14 weeks after conception, your baby's eyes have begun to face forward and slowly move. The ears are close to reaching their final position. Your baby might be able to make sucking motions with his or her mouth. -
Week 16: Baby begins to hear
Eighteen weeks into your pregnancy, or 16 weeks after conception, your baby's ears begin to stand out on the sides of his or her head. Your baby might begin to hear. -
Week 17: Baby's uterus forms
Nineteen weeks into your pregnancy, or 17 weeks after conception, a greasy, cheese-like coating called vernix caseosa begins to cover your baby. The vernix caseosa helps protect your baby's delicate skin from abrasions, chapping and hardening that can result from exposure to amniotic fluid. -
3rd Trimester
The start of the 3rd Trimester -
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Third Trimester
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Week 26:Baby's eyes open
wenty-eight weeks into your pregnancy, or 26 weeks after conception, your baby's eyelids are partially open and eyelashes have formed. Your baby is gaining weight, which is smoothing out many of the wrinkles in his or her skin. -
Week 27: Baby's bones are fully developed
Twenty-nine weeks into your pregnancy, or 27 weeks after conception, your baby's bones are fully developed, but they're still soft and pliable. -
Week 28: Baby's eyes are wide open
Thirty weeks into your pregnancy, or 28 weeks after conception, your baby's eyes are wide open a good part of the time. Your baby might have a good head of hair by this week. Red blood cells are now forming in your baby's bone marrow. -
Birthday
After 9 long months, I come out of the womb.
