Baby Development in the Womb

Ultrasound image of developing fetus

It's amazing to think about baby development in the womb and how a few cells grow into a human being in just nine short months. Many of the changes happen unnoticed as your belly grows to accommodate your growing baby.

About Baby Development in the Womb

During pregnancy, your future child will develop at an astonishing rate. This is an important time to make sure you are eating a healthy diet, taking your prenatal vitamins, and getting good prenatal care. These three steps can help reduce the chance of birth defects and set your baby on the right path to a healthy life.

First Trimester

Your first trimester begins with your last menstrual period. During the three weeks after your period, your body ovulates and, if the timing is right, the egg is fertilized. At this point, there is a lot happening that you are not even aware of as the cells divide to form an embryo. Next, the groups of cells pass through the fallopian tube on their way to the uterus to begin baby development in the womb.

The fourth week is when things really start happening. This is also when you can start taking pregnancy tests and expect to get a positive result. Your baby is being fully protected from the placenta, which just developed this week. Your baby is very tiny, just about the size of a pinhead, but he's developing layers that will turn into the digestive system, bones, and heart.

At the trimester's halfway mark, the baby's development in the womb is right on track. Genitals have formed and you'll soon be able to see them on an ultrasound. Your baby has started developing some major organs, like the liver, kidneys, and spinal cord. Your baby's arms and legs can move, and he has plenty of room to stretch because he's only 3 inches long at this point.

In the end of your first trimester, your baby's fingers and toes are fully formed, along with his eyes, ears, mouth, and nose.

Second Trimester

By the start of your second trimester, your pregnancy is probably no longer a secret. You've also had to ditch the pre-pregnancy clothes for maternity wear.

It's only fitting that you need to expand your wardrobe during these months as there is a tremendous amount of growth going on behind the scenes. Baby development in the womb is at full pace, with the addition of hair, both on the head and the body, bone development, and a fully pumping heart.

When you hit week 20, your baby will weigh close to 9 ounces and is about 8 inches in length. By now, you can probably feel him moving around, so don't be surprised by some bumps in the night. Baby hiccups could also be in full effect and getting a good night's sleep might become more difficult since some unborn babies seem to get more active at night.

At the last week of this trimester, your baby should be about 12 inches long and 1 1/2 pounds.

Third Trimester

Although the third trimester seems harder for moms, your baby gets to take a break from all that baby development in womb he's been going through. Until your delivery, your little guy gets to just sit back, relax, and grow.

He'll gain at least four pounds during this trimester, possibly more depending on the size of his parents. He'll also grown anywhere from five to eight inches.

Once your baby is fully formed and ready to make his appearance to the world, your labor will start. Just a few hours later, you'll get to see firsthand how baby development in womb turned into a living, breathing, beautiful creature.

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Baby Development in the Womb