First Trimester: The First 12 Weeks Of Pregnancy
Did you know that everything about you — including how tall you would be, the colour of your eyes, and the colour of your skin, was all determined at the time of fertilisation? The fate was sealed on whether you were to become a boy or a girl, have straight or curly hair, or big or small feet.
If you are newly pregnant, it might seem like nothing is happening since you can’t visibly see it, but the first trimester of pregnancy is full of wonderful and exciting developments inside the quiet place of your womb. Month by month, your baby is growing safely and comfortably until birth.
The first 12 weeks of your pregnancy are known as the first trimester. Within a week of conception, the fertilised egg, (called a blastocyst) which is about the size of a pen tip, makes its way to the uterus. The cells of the egg are arranged into groupings. The inner cell mass becomes a baby, and the outer cell mass becomes the amniotic sac and the placenta – that’s where the baby will be getting all of its nutrients and oxygen. Once the egg reaches the uterus, the blastocyst then sheds its outer casing and burrows into the wall of your uterus.
Around week 5, your developing baby is now the size of a sesame seed and the cells begin organising and arranging, giving shape to the young embryo, and its primitive organs begin forming. Your baby’s spinal cord is now visible through its translucent skin, and baby’s circulatory system also forms.
Between weeks 5 & 6 of your pregnancy (22 days after conception), your baby’s heart begins beating. Arm buds and legs also begin to appear.
At the 6 week mark, your baby has tripled in size since conception, and is now the size of a lentil! Facial features are formed, and the heartbeat has a regular rhythm.
By week 7, your baby is the size of a coffee bean. It has a mouth, nostrils and arms.
At 8 weeks, he or she is the size of a blueberry and has formed webbed hands and feet. Just one week later, your baby’s organs are now formed and begin to develop. No wonder you’re feeling so tired all the time! Your little one is looking more human every day, with protruding limbs and fingers, a mouth, nose, and tiny earlobes. This is a lot of growth considering the baby is only about the size of a grape at this stage.
By 12 weeks, your baby will be 6cm long, the limbs are now complete and your baby’s ears are forming. While you may not look noticeably pregnant, so much has happened already in the growth and development of your baby, as you begin to move into your second trimester.
Many women see a decrease in fatigue and nausea and an energy burst as all this hard work of the first trimester is finished.
