Week 6This week's major developments: The nose, mouth, and ears that you'll spend so much time kissing in eight months are beginning to take shape. If you could see into your uterus, you'd find an oversize head and dark spots where your baby's eyes and nostrils are starting to form. His emerging ears are marked by small depressions on the sides of the head, and his arms and legs by protruding buds. http://www.babycenter.com/6_your-pregnancy-6-weeks_1095.bc
Week 9You are in week nine of pregnancy. (seven weeks from conception)•The embryo has grown to measure 30 mm (1.2 inches) in length.
•The fingers and toes are well defined. Cartilage and bones begin to form.
•The upper lip as well as the nose tip is being formed.
•The tongue begins to develop and the larynx is developing.
•The eyelids are developed, although they stay closed for several months.
•The main construction of the heart is complete.
Week 12The most dramatic development this week: reflexes. Your baby's fingers will soon begin to open and close, his toes will curl, his eye muscles will clench, and his mouth will make sucking movements. In fact, if you prod your abdomen, your baby will squirm in response, although you won't be able to feel it. His intestines, which have grown so fast that they protrude into the umbilical cord, will start to move into his abdominal cavity about now.http://www.babycenter.com/6_your-pregnancy-12-weeks_1
Week 16Get ready for a growth spurt. In the next few weeks, your baby will double his weight and add inches to his length. Right now, he's about the size of an avocado: 4 1/2 inches long (head to rump) and 3 1/2 ounces. His legs are much more developed, his head is more erect than it has been, and his eyes have moved closer to the front of his head. His ears are close to their final position, too. The patterning of his scalp has begun, though his locks aren't recognizable yet.
Week 19Fetus is around 6.5 inches (17cm) and 9 ounces (250gm).
Your placenta continues to grow and nourish the baby.
Features of your baby's heart, should be visible during an ultrasound.
Your baby's genitals are distinct and recognizable.
Scalp hair has sprouted and continues to grow.
Week 23He or she measures over 28cm and weighs up to 550 grams.
The baby is over 11 inches tall, weighs about a pound.
The eyebrows are visible.
The child can successfully suck.
Bones located in the middle ear harden.
Week 26The baby measures 14 inches long and weighs over 1.7 pound.
Baby measures 35.5cm long and weighs over 760 grams.
The feet are 2 inches (5cm) long. Hands are very active.
The baby's eyes begin to open around this time.
Week 31Baby weighs 3.5 pounds and measures 16.5 inches from the head to heel.
Baby's weight is about 1.6 kg and length around 42cm.
The eyes have now completely opened and are responding to light and darkness.
A loud noise near you may cause your little one to jump.
Week 36During the first six weeks of the third trimester, your baby will more than double in size–growing from approximately 1.5 to 3.5 pounds. He will also grow in length from about 14 inches to almost 17 inches. The baby's growth during this period is an important indicator of his health.
Week 40By the end of this week, your baby will be about 14 inches or 360 millimeters in length from crown to rump and weigh almost 7.5 pound or 3400 grams. Remember however, that healthy babies come in all sizes.