Fetal Development

Brittney - posted on 01/23/2013 ( 1 mom has responded )

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Week Twenty: The halfway point

Congratulations!
You are halfway through your pregnancy, 20 weeks marks the midpoint. Remember, pregnancy is counted as 40 weeks from the beginning of your last period if you go full term.

You are 20 weeks pregnant. (fetal age 18 weeks)
Baby now weighes about 11 ounces and is roughly 7 inches long.
Baby is 17cm long crown to rump, and weighs about 310 grams.
The baby can hear and recognize the mother's voice.
The mother will probably start feeling the first fetal movements.
The toenails and fingernails are growing.
The growth of hair on the rest of the body has started.
The skin is getting thicker.
The heart can now be heard with a stethoscope.
Your baby may react to loud sounds. Baby can actually hear noises outside of the womb. Familiar voices, music, and sounds that baby becomes accustomed to during their development stages often are calming after birth. This is an important time for sensory development since nerve cells serving each of the senses; taste, smell, hearing, sight, and touch are now developing into their specialized area of the brain.

Your baby now weighs about 11 ounces and at roughly 7 inches long they are filling up more and more of the womb. Though still small and fragile, the baby is growing rapidly and could possibly survive if born at this stage.

Note: Babies are measured from the crown (or top) of the head to the rump (or bottom) until about 20 weeks. After that, they are measured from head to heel. This is because a baby's legs are curled up against the torso during the first half of pregnancy and very hard to measure.

Weight: 10.6 ounces - 300 grams
Length:
(crown to rump) 6.5 inches - 16.5 cm
(crown to heel) 10 inches - 25.5 cm.

Week Twenty One: Nourishment evolves

You are 21 weeks pregnant. (fetal age 19 weeks)
Length is now measured crown to heel.
The fetus has grown to 10.5 inches (27 cm) - 12.7 ounces (360 grams).
It is now gaining weight steadily, with fat being added to the body.
Bone marrow has started making blood cells.
Their small intestine is starting to absorb sugars.

Your baby's bone marrow has started making blood cells, a job done by the liver and spleen until this point. The placenta has provided nearly all of your baby's nourishment, now your baby will begin to absorb small amounts of sugar from swallowed amniotic fluid.

Based on the size of baby's head, which is about 2 inches (5cm), the date of birth can be determined to within one week. The fetus is steadily gaining fat and has grown a whitish coat of a slick, fatty substance to protect skin in amniotic fluid and to ease delivery.

In girls, the vagina is formed and the ovaries already contain over six million eggs which will be reduced to about 400 by the time of puberty. For boys, the testes begin to descend from the abdomen this week. (Boys don't produce sperm until puberty).

The baby can hear and recognize the mother's voice, and may respond to some types of music.

Week Twenty Two: Taste buds develop

You are 22 weeks pregnant. (fetal age 20 weeks)
The fetus reacts to loud sounds.
Baby starts having a regular sleeping and waking rhythm.
The mother's movements can wake her baby.
Taste buds are forming on your baby's tongue.
The baby is 28cm long (crown to heel) and weighs over 450 grams.
The weekly weight gain has increased to around 70 grams.
Your baby is about 11 inches long and weighs in at about 1 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 or her to be able to hear you.

By this week, your waistline is definitely gone. The top of your uterus is now about 1 inch (3cm) above your bellybutton. Your enlarging abdomen is not too large and doesn't get in your way much. You're still able to bend over and to sit comfortably. Walking shouldn't be an effort. Your friends and relatives can tell you are pregnant. It would be hard to hide your condition.

The baby is about 11 inches (28cm) long (crown to heel) and weighs in at about 1 pound (450g).


Week Twenty Three: Sense of balance develops

You are 23 weeks pregnant. (fetal age 21 weeks)
He 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.
Your baby does a regular 'workout' inside your womb. He or she turns from side to side and head over heels. Thanks to a fully developed inner ear, which controls balance, your baby may have a sense of whether he or she is upside-down or right side up in the womb.

Skin pigment is now forming. The fetus is now proportioned like a newborn except it is a thinner version of a newborn baby since its baby fat has not developed much yet.

The pancreas, essential in the production of hormones, is developing steadily. Baby has begun producing insulin, important for the breakdown of sugars.

If born now, your baby would have a 20% chance of survival, the odds going up with each passing day. By this week, your baby weighs a little over 1 pound (500g). Its crown to heel length is 11 inches (28cm).

Week Twenty Four: Practices breathing

You are 24 weeks pregnant. (fetal age 22 weeks)
The child is now gaining around 3 ounces (90 grams) a week.
Baby weighs about 1.3 pounds and is 12 inches long.
Baby weighs about 600 grams and is 30cm (crown to heel) long.
The eyelids can be seen very clearly.
If born at this stage is officially considered viable, they may well be able to survive.
The lungs are developing branches of the respiratory tree and cells that produce surfactant. This is a substance that helps the air sacs inflate easily and also keeps the small air sacs in our lungs from collapsing. The baby practices breathing by inhaling amniotic fluid into developing lungs. 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.

Baby gains about 3 ounces this week. The weight is in muscle, bone mass and organs. The body begins to fill out with its appearance increasingly becoming more like that of a newborn. Taste buds begin to form. If mom drinks something strange or bitter, baby may be observed showing his or her distaste.

Little creases have appeared on his palms. The muscular coordination of the hands has improved as they sucks their thumb. Over the next week or so, the sweat glands will be forming in the skin.

Mother: Gentle exercise will keep you fit and help you cope with the delivery. Pregnancy yoga, pilates or go for a swim, aquanatal classes are a great way to make friends.

Baby now weighs about 1.3 pound (600gm) and is around 12 inches (30cm) long.

After this week your baby is officially considered viable. 36% of babies can survive premature birth at 24 weeks - However, serious complications are still possible.


Week Twenty Five: Exploration continues

You are 25 weeks pregnant. (fetal age 23 weeks)
The unborn child is 34 cm in length and weighs almost 690 grams.
Baby is around 13.5 inches in length and weighs 1 and half pounds.
Bones are becoming solid, hands are now fully developed.
The brain is growing rapidly, the brain cells are starting to mature.
The sexual organs are fully developed.
Baby is now pretty well built portion wise even though it still has little body fat and its skin is thin. The structures of the spine begin to form -- All 33 rings, 150 joints and 1000 ligaments. The tiny brain is growing rapidly, and the baby is starting to fill the space in your uterus. The uterus is now about the size of a soccer ball and mom looks pregnant.

Your baby's hands are now fully developed, although some of the nerve connections to the hands have a long way to go. Dexterity is improving. Your baby can make a fist and clasp objects placed in palm. Exploring the structures inside your uterus may have become baby's prime entertainment. Fascinated by the amount of tactile stimulation a fetus gives itself; it touches a hand to the face, one hand to the other hand, clasps its feet, touches its foot to its leg, its hand to its umbilical cord. Twins will explore each other and begin their bonding.
See: Twins 3D sonagram movie.

Blood vessels of the lungs develop. Your baby's nostrils begin to open. The nerves around the mouth and lip area are showing more sensitivity now. Their swallowing reflexes are developing. Baby can hear sounds outside the womb and the brain cells are starting to mature also. Already it can learn and remember and can recognise its mother and fathers voice. The inner ear bones have hardened so hearing is more acute. Baby may hear your partner's voice more easily than yours, as baby is sensitive to a deeper pitch.

Babies born at 25 weeks of pregnancy have about a 50% chance of survival.


Week Twenty Six: Second trimester ends this week

You are 26 weeks pregnant. (fetal age 23 weeks)
The 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.
The fetus makes breathing movements, but there is no air in the lungs yet. Hands are active and muscle coordination is such that they can get a thumb into the mouth. Thumb sucking calms the baby and strengthens the cheek and jaw muscles.

The fetal brain scan will show response to touch. Touching and playing with the baby is possible now, as they may respond to your touch through your belly wall. Brain growth continues with brain wave activity for the visual and auditory systems starting to develop. Baby is probably very active in the womb, as the most active weeks are typically between weeks 24 and 28.

You may begin feeling your belly tighten and relax at odd moments or irregular intervals. These are Braxton Hicks contractions. They are painless and help the uterus prepare for the birth. Many babies have developed a predictable routine for sleep and active periods. Twins may have entirely different routines from each other.

If your back is feeling the strain of your growing belly, try doing some pelvic rocks to relax it. Stand with your back against the wall, knees slightly bent. As you inhale a breath, press the small of your back against the wall. Exhale and relax your back. You may be experiencing shortness of breath as the uterus is very close to the rib cage at this stage. Some moms are not able to fully expand their rib cages; however, this does not negatively affect the baby in any way.

The end of week 26 marks the end of month six, which is the last month of the second trimester.

MOST HELPFUL POSTS

Mercedes - posted on 02/11/2013

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Awww. Week 25, I am definitely feeling that little explorer! That is so cute that he can hear me and recognize my voice now!!!
Also, yay for looking pregnant.

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