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First trimester

The 1st trimester of your pregnancy

Congratulations, you are pregnant! An exciting time for you and your body is about to begin. Many things will change for you. This may sometimes be unfamiliar to you at first, and some things will surprise you. This is quite normal and happens to most moms-to-be. Because at the same time as your physical changes, a little person is developing in your belly. What a miracle!

How to calculate the first week of pregnancy

Many pregnant women are surprised to learn at their first doctor’s appointment that they are already in the 7th or 8th week of pregnancy. How can this be? It’s simple: it’s because the week of pregnancy is calculated according to the 1st day of your last period. If you miss your period, you are then mathematically already in the 4th or 5th week of pregnancy.

This is how your baby develops in the first trimester:

  • In the 4th week of pregnancy, the placenta develops.
  • In the 5th week of gestation, the fetal organs begin to form. Nutrients are transported from the placenta to your baby via the umbilical cord. The crown-rump length, i.e. the length from the crown to the rump, of your baby is now about 0.05 in.
  • In the 6th week of gestation, the so-called “neural tube” is formed, from which the brain and spinal cord will later develop. Organs such as kidneys, liver, heart, and lungs are formed. The extremities develop in the form of buds.
  • From about the 7th week of pregnancy, a fetal heartbeat can already be seen in the ultrasound. The brain now begins to develop. All organs continue to mature.
  • In the 8th week of pregnancy, even the sensory organs are already developed and communicate with the fetal brain. Further intestinal development also begins now.
  • In the 9th week of pregnancy, the 4 limbs slowly develop from the buds.
  • The 10th week of gestation is characterized by the formation of the face. Forehead, nose, lip, jaw, and palate are now visible. Your baby is now 1.22 in from crown to rump.
  • In the 11th week, the genitals begin to form.
  • In the 12th week, your baby can even open and close its eyes. On the ultrasound, you can now see how your baby is moving. It now has 2.13 in. and weighs about 0.49 oz.

Second trimester

Third trimester