Each week of a woman’s 40 week pregnancy is marked by a number of significant changes. The following is a list of a few pregnancy week by week highlights that take place during the first 20 weeks:

Week 1: Week by week pregnancy notes the first trimester. The sex of the fetus is determined during week one.

Week 2: The embryo attaches to the placental wall of the uterus.

Week 3: The expectant mother experiences early pregnancy symptoms such as fatigue, breast sensitivity, and nausea. The cardiovascular system and central nervous system begin to develop.

Week 4: The fetus ears and limbs start to form. The limbs are much like little buds.

Week 5: The mother is experiencing more nausea. The embryo is about 2 – 3 inches in length. The embryo’s head is the biggest feature because the brain is developing.

Week 6: The mother’s breasts become bigger and sensitive. The heart of the fetus is beating.

Week 7: Fetus development includes eyelids, fingers, toes, and mouth.

Week 8: The fetus blood vessels are developing. The fetus is starting to look like a baby.

Week 9: The uterus will grow significantly to that of the size of a grapefruit.
The toes and fingers of the fetus are prevalent.

Week 10: The mother’s weight will increase. The will be about 1.5 inches long.

Week 11: The uterus has become more visible. Major organs are developing. The sonogram is usually given.

Week 12: The increase in weight is visible. The fetus can suck its thumb and swallow. It can be seen breathing with chest movements.

Week 13: The mother may develop stretch marks. The fetus is moving. Its organs are working. Teeth and bones are developing.

Week 14: Week by week pregnancy notes the second trimester. Fetus is about a pound in weight.

Week 15: The fetus will respond to sounds such as the heartbeat. It also has a hair covering called “Lanugo.”

Week 16: The fetus is moving more often.

Week 17: The mother weight is increasing. The legs and arms of the fetus are developed. It can differentiate between certain tastes and weighs about 6.5 ounces.

Week 18: The mother may have lower back pain. The fetus will respond to outside noises and will weigh up to 8.6 ounces.

Week 19: A mother may feel faint. The fetus’ baby teeth are developing and it weighs about 10 ounces.

Week 20: Fetus is covered with a greasy substance called Vernix.

This entry was posted on Sunday, February 27th, 2011 at 8:14 am and is filed under Pregnancy. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.