Organ development
Brain
The first thing to develop is the brain, around 18 days the nural tube which is the foundation of the the spinal cord and
brain starts to form. By six weeks the brain is out growing the rest of their body. As the month progress the brain becomes
more and more complex. From 29 weeks the baby is aware of their surroundings. By 32 weeks the brain is as advanced as a newborn's
By the end of the pregnancy the babies brain has grown around 100 billion neurons.
Heart
At around three weeks the baby's heart is a clump of cells the size of a seed. It springs into life after 22 days. By six
weeks it ha compartments and valves. By week five the heart is pumping around 80 times a minute.
Lungs
Lungs appear at 4 weeks and have divided into segments by six. Around 4 months the blood vessels have formed. They
get oxygen from the placenta so the air sacks stay closed but they practice breathing
Digestive system
In week 4 they develop a basic digestive tract from the mouth to the stomach. The by week 8 it is fully developed.
Liver and kidneys
The forst set of kidneys appear in week 4 but do not function. the second appear a few days later and filter blood for
most of the second month. In the 5th week the final set develop. By week nine the baby's kidneys produce urine and function
fully. At this point the liver is creating most of the red blood cells. By six months all of the organs are in place
and they will continue to develop over the next 3 months
Stages of development
1st Trimester
By the end of this trimester, your baby is about three inches long and weighs about half an ounce. The eyes move closer
together into their positions, and the ears also are in position. The liver is making bile, and the kidneys are secreting
urine into the bladder. Even though you can't feel your baby move yet, your baby will move inside you in response to pushing
on your abdomen.
2nd Trimester
By the 26th week, your baby will weigh about 1 ¾ pounds and be about 13 inches long. With this growth comes the development
of your baby's features, including fingers, toes, eyelashes, and eyebrows. Around the fifth month, you might feel your baby
move! By the end of this trimester, all of your baby's essential organs like the heart, lungs, and kidneys are formed.
Third Trimester
Your baby is still growing and moving, but now has less room in your uterus. Because of this, you might not feel the kicks
and movements as much as you did in the second trimester. Even before your baby is born he or she will be able to open and
close his or her eyes and might even suck a thumb.
What a miracle it all is !
