Pregnant week by week: What happens inside your belly during your 40 weeks of pregnancy? Here you can follow your pregnancy week by week. From the time your baby is a tiny sprout until he or she is full-term and ready to meet the world.

Vitamin D, folic acid, iron, vitamin pills.... There are many supplements you need to take as a pregnant woman! See the Health Authority's recommendations.

Pregnant week by week

Here you can follow your pregnancy week by week. The city develops and grows at a rapid pace during the 40 weeks from conception to birth. It's an exciting journey that can also be tough to get through.

Here we have written about what happens in each week of pregnancy. The overview is divided by the three trimesters.

How far along are you in your pregnancy?

Pregnancy is divided into three trimesters.

1st trimester (Weeks 2 through 12)

The 1st trimester of pregnancy is up to and including week 12. In this part of the pregnancy, the egg is fertilised and the foetus develops all its vital organs. During the first 12 weeks, the heart is fully developed, the tail shrinks and the baby looks like a real little person.
In this part of the pregnancy, the baby is most sensitive to alcohol and the risk of miscarriage is highest until week 7-8.

You may experience nausea, gas, nausea, decreased sex drive, mood swings and many thoughts about the future as a parent.

2nd trimester (weeks 13 through 28)

From week 13 - 28 you are in the second trimester of your pregnancy.During this part of your pregnancy you will be offered both a neonatal scan and a malformation scan.

Baby grows from the size of a plum to a baby of about 1 kg. The stomach grows and the body may hurt. Remember to rest, but also make sure you keep moving, for example with pregnancy swimming.

3rd trimester (week 39 until birth)

From week 28 until term is the last part of pregnancy and is called week 40.

Most people eventually experience some discomfort from pregnancy in the form of contractions and pelvic pain. It is necessary to slow down a little, as you lose your breath more quickly.

Week 36 is the start of the maternity period, when you can slow down and prepare for the baby's arrival.

It can be hard to sleep because of the big belly, so you can be really tired and long for the baby to be born.

When does pregnancy start?

The first day of your last period before pregnancy counts as "week 0" of pregnancy. The day of your almost expected period is therefore week 4+0 (4 weeks and 0 days). On this date, for most people, the pregnancy test will be positive. For others, it will be a little longer before the test shows two bars. It depends on when ovulation and fertilisation took place.

How many weeks pregnant?

The due date is at week 40+0. This means that you are pregnant for 40 weeks. However, babies born from week 37+0 up to 42+0 are considered full-term. It is therefore a good idea to be ready for baby from week 37.

What week am I pregnant?

Many mothers-to-be probably wonder about this, especially at the beginning of pregnancy. You can work out how far along you are in your pregnancy from the first day of your last period. From there, count the weeks until today.

When you e.g. enters week 13, it is called 13+0. The next day you are 13+1, and then you are in the 14th week until 14+0, when week 15 starts.


  • The Baby Institute
  • Libero
  • Personal experiences