Baby Developing inside you

Fetal Development

Baby developing inside you
over the weeks and months
baby inside


Weeks, Months and Trimesters Guides

Your Weekly Guide  Your Monthly Guide Your Trimester Guide

Third Trimester:

Full term pregnancy is considered 40 weeks counted from the first day of a your last period. This is broken down into weeks, and divided into three equal parts called trimesters.
The seventh, eighth, and ninth months are the third and final trimester of pregnancy.

For more information on development, use the drop down menus above or the weeks links below.

28 weeks27 weeks - The fetus weighs now just over 2 pounds and is about 14 inches long. The baby's eyes begin to open around this time.

28 weeks - The fetus has his own regular intervals for sleeping and being awake. It also opens and closes its eyes and may suck a thumb.

29 weeks - Your baby now weighs about 2 1/2 pounds and is about 15 inches long from head to heel. His muscles and lungs are continuing to mature, and his head is growing bigger to accommodate his brain, which is busy developing billions of neurons. Baby hears things better from the vibrations all around, and can now distinguish real sounds and voices. Don't forget to continue to 'teach' your baby in the womb by exposing to music, literature, and simply talking to him.

30 weeks - For several months, the umbilical cord has been the baby's lifeline to the mother. Nourishment is transferred from the mom's blood, through the placenta, and into the umbilical cord to the fetus. The fetus now weighs about 3 pounds.

31 weeks - Now it is time for the baby's lungs and digestive tract to be very near of being mature. Baby's weight gain will exceed its growth in length from now on. Baby may move to the rhythm of music. Studies with heart rates show that they may also prefers some types of music to others -- already!32 weeks

32 weeks - During this time the baby sleeps most of the day. The baby will now weigh about 4 pounds. The uterus getting to be too small for the baby to move so you may have notice a decrease in your baby's movements. The baby is still trying to move frequently but it just doesn't have enough room. The baby can also now turn its head from side-to-side. The baby's organs are continuing to mature.

33 weeks - The fetus is now about 18 inches long and weighs 4 1/4 pounds. The baby is using it's lungs to practice breathing by inhaling amniotic fluid. The baby's hair is also growing.

34 weeks - The baby now weighs about 5 pounds and is approximately 19 inches long. It has probably already take the head-down position by this time. The skull bones are still pretty flexible and not completely joined to help to ease exit out of the narrow birth canal. The baby's skin is also becoming less wrinkled and red.

35 weeks - The baby is now about 19.5 inches long and weighs over 5.5 pounds. The baby's hearing is now mature. The baby's body is growing round because of developing fat layers.

38 weeks36-37 weeks - The baby's weight is now about 6 pounds and and the height is about 20 inches. You may now notice that it sometimes may feel like the baby is gradually dropping. This is called lightening. The feeling comes from increased pressure in the lower abdomen.

38-40 weeks - Your pregnancy is considered full term now (anytime between 38-42 weeks is full-term). Most of the baby's skin downy coating has now disappeared. At the time of birth, most babies weigh about 7.5 pounds, and are 18-20 inches long, but it can vary with each baby, and there is no cause for concern. At birth the placenta will detach from the side of the uterus and the umbilical cord will stop working when the child takes his first breaths of air outside of uterus. The child's breathing will trigger changes in the heart that will force all blood to go through the lungs.

Week 41 and Week 42 you are considered full-term [overdue].
The ninth month is the last month of pregnancy and is the end of the third trimester.

Stages of Labor and Birth

~   Contractions   ~   Contractions Timer

third trimester

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Week By Week Pregnancy Calendar

First Trimester
Week 1   Week 2   Week 3   Week 4   Week 5   Week 6   Week 7  
Week 8   Week 9   Week 10   Week 11   Week 12   Week 13
Second Trimester
Week 14   Week 15   Week 16   Week 17   Week 18   Week 19   Week 20  
Week 21   Week 22   Week 23   Week 24   Week 25   Week 26
Third Trimester
Week 27   Week 28   Week 29   Week 30   Week 31   Week 32   Week 33  
Week 34   Week 35   Week 36   Week 37   Week 38   Week 39   Week 40   Week 41   Week 42

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