4. part “pregnancy week by week” described how the embryo burrowed into the uterine wall and grows bigger every day. Here we have the third week after fertilization, the beginning of the week 5 of your pregnancy.
5 weeks pregnant
Menstruation has not appeared. You may have slightly swollen breasts, the areola darkens and you can even recognize the pigment spots. You may also have signs similar to premenstrual symptoms and nausea. Tiredness is very common in this period, so do not be surprised that you need to go to bed much earlier than usual.
What happens in the week 5?
The embryo is still very small, but already forms into the tube shape in the firth week of pregnancy. The head and the tail get recognizable.
Around 17th day of the development, the embryo itself is differentiated into three layers. These will be the basis for the future tissues and organs. At this stage, the placenta has a lot of rounded columns also called chorinic villi.
They will later transform into a temporary organ that will take care of the exchange of substances between you and the baby. It will supply the embryo with oxygen and nutrients through a vein and two arteries in the umbilical cord and remove carbon dioxide at the same time.
We can shortly say that the brain, spinal cord, muscles and bones are formed in the the third week of the child’s development (in the 5th week of pregnancy). The fetus is approximately 1.25 mm large.
At the end of the 5th week of pregnancy, the first primitive segments outline in the area of the future child’s neck. These will give rise vertebrae of the spine. Blood circulation is forms in the emryo. It consists of a single heart tube which receives the fetal blood through the primitive umbilical vein from the placenta. The embryotic heart begins beating and the blood begins to flow in the heart and blood vessels. Origin of the brain is still unfinished.
Week 5 and first visit of gynecologist
If you have not done so yet, it is the high time to make an appointment with your gynecologist. He will do the examination and ask you about a so-called anamnesis. He will ask you about your health (suffered and hereditary illness, operations or births) and details about the father of the child and other family members. The doctor will determine your due date and invite you for the next checkup.