This image shows just how curled up the embryo is at this stage. The head end of the embryo is on the left. The embryo now has 22 pairs of somites (building blocks of the musculoskeletal system) running along the back.
This week your baby begins to grow rapidly and will become much more recognizable as a baby over the next five weeks. There are three types of cell, each committed to a separate function. The first will form the skin and nervous system; the second forms blood vessels, muscles, and bones; the third forms the entire digestive system.
At this stage, it is the cells responsible for the spine and nervous system that are at work. Changing shape from a flat disk, the embryo starts to curl up. The edges of the groove that has already partially formed along the back gradually start to meet, closing and fusing to form a tube, which will become the brain and spinal cord. The last parts of the tube to close are at the very top of the head and then the base of the spine, two days later.
Being careful to get an adequate intake of folic acid in early pregnancy is essential to ensure the neural tube closes completely, with no gaps.
Your first reaction to finding out that your partner is pregnant might be to tell the world. After all, you may be excited or nervous and may want to confide in people who you can trust. Think twice before telling lots of people and don't do so without talking to your partner. Of course your partner may find it hard to hide some aspects of pregnancy, such as morning sickness.
Most importantly, make sure that you are both in agreement that it is the right time to tell others.
You're excited to be pregnant, but should you tell people yet?
Excerpted from Pregnancy Day by Day.
Copyright Â© 2009 Dorling Kindersley Limited.
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