The first twelve weeks of pregnancy are called the first trimester.
Although a pregnancy is not yet very visible from the outside, a lot happens inside your body. From the fertilisation and implantation of the egg to the rapid development of the organs, brain and head of the embryo, the focus is on the fertilisation of the egg.
The fertilised egg cell implants itself in the uterus
The 3rd week of pregnancy is the 1st week of the embryo’s development: your last period was 3 weeks ago and 1 week ago you ovulated and conceived. The blastocyst implants itself in the uterus. It develops an inner and an outer layer.
Am I pregnant or not?
At the end of this week, a normal off-the-shelf pregnancy test can be used to determine whether or not you are pregnant. . If you are pregnant the blastocyst has fully transplanted itself and is covered by the mucous membrane inside the uterus. It forms three layers of cells from which the various organs will develop.
The first heartbeat!
The embryo is now undergoing a particularly critical developmental phase. The head and body can be identified. The beginnings of the arms and legs are clearly emerging.
The clearly elongated C-shaped embryo is floating in the amniotic sac. The spine runs from the neck past the fin-like arm buds to the area where the legs will form. The umbilical cord connects the embryo’s circulation to the placenta.
The embryo is connected to the placenta via the umbilical cord. The face, arms and legs are clearly visible.
Insatiable hunger or loss of appetite?
The external parts of the ears, the tip of the nose and the top lip are already formed. The beginnings of fingers and toes can be seen.
Between the head and body it is possible to distinguish a short, wide neck. The face continues to develop with eyes and eyelids, lips and the beginnings of teeth.
All the vital organs are present
The embryo is becoming more and more like a baby. The head is still disproportionately large. The eyes are covered by eyelids.
Still no baby bump
Your child is no longer as susceptible to harmful influences as it was during the critical phases of organ development. The eyes are facing forwards, the ears have moved upwards. The eyelids remain closed.
The first third of your pregnancy is nearly over, so the most critical phase for you and your child will soon be behind you. With a high forehead and a button nose, the embryo’s face has a clearly distinguishable profil.
If you are eating a balanced diet, you will now gain 1 to 1.5 kg on average every month. The placenta is now fully formed. The foetus is fully formed. It is sucking its thumb.
The child can feel your heartbeat
Your child is still growing rapidly. It is looking more and more like a newborn. You might notice that your previously comfortable pants are starting to pinch around the waist, or your favourite skirt no longer sits as it should.