During the fourth week, your embryo has already found a safe place in the womb and the next few weeks are essential for further growth and development. The embryo starts out as an amazing three-layer structure that later evolves into different body parts. The inner layer forms organs such as the liver and lungs, while the middle layer is responsible for the heart, bones, muscles, kidneys and sexual organs. The outer layer helps form your baby's hair, eyes, skin and nervous system. The placenta begins as a modest yolk sac but has an impressive function. It produces HCG, the pregnancy hormone, and tells your body to stop producing new eggs.

This week you may already consider taking a pregnancy test , although it may still be too early. This is because your body has not yet produced enough pregnancy hormones yet, so the test may be negative, even if you are actually pregnant 💛

It will be some months before the outside world discovers your secret discovered, but you may already be suffering from a bloated belly. This has more to do to do with your intestines than with your embryo, because it is still too small to cause visible changes.