How Your Baby Develops

Fertilization! The sperm and egg join in your Fallopian tube to form a unique human being. That’s 46 combined chromosomes which pre-determines all of a person’s physical characteristics.

Washed into your uterus, the developing embryo searches for a nice place to implant and is only one-sixth of an inch long, but growing quickly.

The heart, no larger than a poppy seed, has been beating since day 18 when a woman is just four days late for her menstrual period, and by 21 days it is pumping, through its own closed circulatory system, blood whose type is different from yours.

Four weeks after fertilization the eye, ear and respiratory systems begin to form. Thumb-sucking has been photographed within the first trimester, at 9 to 12 weeks, by scientists.

Did ya know?
The baby at the fetal stage savors its mother’s meals, first picking up the food tastes of a culture in the womb. And you wondered why you love spicy food so much!

By 8 weeks the embryo grows to 1/2 an inch, the major muscles system develops and she moves gracefully like a good swimmer although you can’t feel it yet.

This tiny human is perfectly developed with long, tapering fingers, feet and toes and whose skin is almost transparent with a highway of delicate arteries and veins visible to the ends of the fingers.

By 10 weeks, 20 tiny baby teeth are forming in the gums, your baby squints, swallows, moves it’s tongue, and if you stroke it’s palm, will make a tight fist. The toes will develop in the next few days and brain waves can be measured and your baby will react to loud noises.

Did ya know?
By nine weeks the developing baby can hiccup and react to load noises. This might explain why I still hiccup at loud concerts.

By the second trimester, your baby is now in its fetal stage and measures 2 1/2 to 3 inches in length. Fully formed the heart rate can be heard with a special instrument called a Doppler and just as adults, the fetal baby can experience the rapid eye movement (REM) sleep of dreams.

From 12 weeks, they can stretch, kick and leap around the womb – well before the mother can feel movement.

The body is more complex than ours. The fetal baby has several extra parts to his body which he needs only so long as he lives inside his mother. He has is own space capsule, the amniotic sac. He has his own lifeline, the umbilical cord, and he has his own root system, the placenta. These all belong to the baby himself and not to his mother, all developed from his original cell.

Did ya know?
Just as adults the baby at the fetal stage experiences the rapid eye movement (REM) sleep of dreams. Okay… why did you say you like REM’s music?

Your baby is coated with soft downy hair called “lanugo” and comes in at about 6 inches in length and weighing 6 to 7 ounces.

Fine hair, eyelashes, and fingerprints are all complete and your baby is all made up!

Awake or asleep, the fetal baby moves 50 times or more each hour exploring her warm, wet compartment by touch.

Your baby touches it’s hand to it’s face, places one hand on the other hand, crosses it’s little feet, places it’s hand to the umbilical cord and sometimes walks around the womb by pushing off with it’s feet.

Did ya know?
Awake or asleep, the human fetus moves 50 times or more each hour exploring their warm, wet compartment by touch. Ever wonder where we got those funky dance moves from?

By 20 weeks your baby will have grown to 1 pound or 454g and though still small and fragile she can hear and recognize her mother’s voice — your voice!

You’ll be feeling the baby move even more and using an ultrasound device the doctor can tell if the child is a girl or a boy.

Although vision is the last sense to develop there is sometimes just enough light filtered through the mother’s tissue that a fetal baby can respond when the mother is in bright light.

From 18 weeks, babies can open their eyes although it was once thought eyelids were fused until 26 weeks.

Did ya know?
Although vision is the last sense to develop there is sometimes just enough light filtered through the mother’s tissue that a fetal baby can respond when the mother is in bright light, like when she sunbathes.

The tender skin is now covered by a waxy substance called “vernix” and the baby continues to practice breathing by inhaling amniotic fluid in preparation for the big day when your baby takes it’s first breath of air.

Eyes begin to part and open occasionally for short periods of time. Hiccups are not uncommon. The baby learns constantly.

After birth it prefers the mother’s voice because she has been listening to mom filtered through the amniotic fluid. From 26 weeks, babies exhibit a whole range of typical baby behavior and moods, including scratching, smiling, crying, hiccuping, and sucking.

Did ya know?
The baby in the fetal stage constantly learns. After birth the baby prefers the mother’s voice but now days the father is talking and singing to babies too. your baby will know you by your voice.

By month’s end, your baby is 14 to 16 inches long and can weigh 2.5 to 3.5 pounds. The organs continue to mature. If you expose your belly to a bright light you may get a quick reaction. The fetal baby can now inhale, exhale and even cry.

Eyes have completely formed, and the tongue has developed taste buds. Your baby’s body fat is beginning to form in preparation for life outside the womb. If born at this time, he will be considered a premature baby and require special care.

Did ya know?
When you see the fetal baby on ultrasound and the mother starts to laugh, you can see the baby, floating upside down in the womb, bounce up and down on its head, bum-bum-bum, like its bouncing on a trampoline. When mothers watch this on the screen, they laugh harder, and the fetus goes up and down even faster. You gotta wonder if this is why we grow up liking roller coasters so much!

Overall growth is rapid this month and your baby may gain as much as a half a pound per week.

At eight months of pregnancy, your baby may weigh from 4 to 6 pounds and is gaining about half a pound per week. Layers of fat are piling on under your baby’s skin. Soon the baby will turn head down in preparation for the coming birth.

Most body organs are now developed with the exception of the lungs and if the baby kicks you’ll not only feel it but also be able to see it on the outside. Tremendous brain growth occurs at this time and the finger nails begin to extend past the fingertips.

Did ya know?
The roots of human behavior begin to develop early — just weeks after conception in fact. Well before a girl typically knows she is pregnant, her baby’s brain has already begun to bulge. By five weeks, the organ that looks like a lumpy inchworm has already embarked on the most spectacular feat of human development: the creation of the cerebral cortex, the part that allows all of us to move, dance, run, speak and sing in a real human way. Well… most of us sing in a real human way.

By nine months, most of your baby’s bones have hardened, although your baby’s skull is still pliable.

The baby shedding most of the downy covering of hair as well as the creamy vernix caseosa that covered it’s body. The next few weeks are spent just putting on weight.

Soon your baby settles down lower in the abdomen in preparation for birth and may seem less active. Skin is pink and smooth and the child measures 19 to 20 inches in length. Lungs are mature and at approximately 8 pounds the baby is ready for life outside your womb. Soon you’ll meet your baby face to face!

Did ya Know?
There are some really cool photos of the baby in utero, using the latest embryoscopy and 3-D ultrasound. Have a look for yourself… there is nothing gory about these, girls!

See theses images here: Images in the Womb.