Baby developing inside you
over the weeks and months
Weeks, Months and Trimesters Guides
|Full term pregnancy is considered 280 days counted from the first day of a your last period. |
This is broken down into 40 weeks, or divided into three equal parts called trimesters.
The fourth, fifth, and sixth months are the second and middle trimester of pregnancy.
For more information on development, use the drop down menus above or the weeks links below.
13 weeks - The fetus is now 3 inches long and weighs just an ounce. The baby's unique fingerprints are already in place. The muscles lengthen and become organized. Soon you will start feeling the first flutters of the unborn child kicking and moving within.
14 weeks - The fetus is 3 and half inches (9cm) long. Weight is about 1 and half ounces (45 grams). The eyes are slowly moving towards the centre of the face and the nose is more pronounced. The ears are developing, the cheekbones are visible and the first hair is appearing.
15 weeks - The fetus has an adult's taste buds and may be able to savor the mother's meals. The baby's thin skin is covered with ultra fine, downy hair (Lanugo) that usually disappears before birth.
16 weeks - The foetus weighs now three and half ounces and is 5 inches crown to rump. The baby can grasp with his hands, kick, or even somersault.
17 weeks - The baby's circulatory system and urinary tract are up and operating. The lungs are inhaling and exhaling amniotic fluid.
18 weeks - The foetus is now 6 inches long and weighs 6 ounces. With and ultrasound you can decide whether or not to find out the sex of your baby if your baby is in a position that reveals the genitals. If female, the vagina, uterus, and fallopian tubes have formed. If male, the genitals are discernable.
19 weeks - Baby's legs are reaching their relative size and with the increase muscle development occurring as well, you will start feeling much more than tiny flutter kicks soon. If you have not felt movement yet, you will soon. Your baby will increase its weight by more than 15 times between now and delivery.
20 weeks - The child can hear and recognize the mother's voice. This is an important time for sensory development since nerve cells serving each of the senses--taste, smell, hearing, seeing, and touch are now developing into their specialized area of the brain. Though still small and fragile, the baby is growing rapidly and could possibly survive if born at this stage.
21 weeks - The fetus is steadily gaining fat to stay warm and has grown a whitish coat of a slick, fatty substance to protect skin in amniotic fluid and to ease delivery.
22 weeks - The fetus is now about 11 inches (28cm) long (crown to heel) and weighs about 3/4 of a pound. The eyebrows and eyelids are fully developed, and the fingernails cover the fingertips. Sounds from a conversation are loud enough to be heard by the fetus in the uterus. If you talk, read, or sing to your baby, it's reasonable to expect him to be able to hear you.
23 weeks - The fetus is now proportioned like a newborn except he is a thinner version of a newborn baby since its baby fat hasn't developed yet. The baby weighs about a pound and is around 12 inches in length.
24 weeks - The unborn baby is covered with a fine, downy hair and the skin is protected by a waxy substance. Some of this substance may still be on the child's skin at birth at which time it will be quickly absorbed. The baby practices breathing by inhaling amniotic fluid into developing lungs.
25 weeks - The fetus weighs over 1 1/4 pounds. It is now pretty well built portion wise even though it still has little body fat and its skin is thin. The brain is growing rapidly, and the baby is starting to fill the space in your uterus.
26 weeks - The fetus makes breathing movements, but there's no air in the lungs yet. The fetal brain scan will show response to touch.
Week 26 and the sixth month is the end of the second trimester.
<<< First Trimester | Third Trimester >>>
Week By Week Pregnancy Calendar
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
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
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