Physiology in the First Trimester at a glance

The first trimester

Pregnancy is a period of significant physical and psychological changes. Here at Hera Family Care we are by your side on this journey so that you can be prepared as a family for these changes.

The first trimester is very important and constitutes the first 12 weeks of pregnancy. 

The period from conception, that is, about three weeks after the fertilisation of the ovum, to 9 weeks is called the embryonic period. 

Realistically it is quite difficult to determine exactly when conception occurred. Using the knowledge we have about your cycle we can make a calculation of the possible date of conception.

The exact gestational age of the fetus is calculated more confidently with the ultrasound of the first trimester, which  gives us the “probable date of birth” or the “estimated due date” and other information about the well-being of the fetus in this phase.

What weight does the baby have?

Here your baby has a weight of 1 gram up to 23-25 grams in total.

How does the baby develop in the First Trimester?

Your baby’s heart starts beating from about 6 weeks while the central nervous system ,to which their basic vital functions are attributed, begins to form from the 7th week onwards. 

During the 6th week, the limbs also begin to form, while on the 9th to the 10th week, the appearance of the eyes and ears of the fetus begins. In this phase, the fetal teeth appear inside the gums and the oral cavity.

The first trimester of pregnancy is considered the most important for the creation of the fetus, so it requires special attention especially with food, medications and other substances such as tobacco and other recreational drugs which are not recommended in pregnancy.

At this stage, the woman may have nausea during the day, which is perfectly normal, however, if you see that you are unable to eat properly, you should contact the relevant healthcare professionals immediately. 

Pro tip: A good trick  is to frequent small meals. Snack!Snack!Snack!

It is also a period of particular hormonal changes. Especially if it is your first pregnancy, your feelings may be difficult to process. Here at Hera Family Care we support you in every change. Join us at our pregnancy education classes for detailed information about the first trimester! 

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