Pregnancy Calendar: all about the journey from conception to the birth of your baby

Are you planning to get pregnant or already expecting a baby?  Our HiPP Pregnancy Calendar accompanies you on this journey – on the following pages you can read everything about baby’s development in your womb. Get a week by week overview of what’s happening during your pregnancy.


Week 1-2



Week 3

< 1 mm


Week 4

< 1 mm


Week 5

1-2 mm


Week 6

2-3 mm


Week 7

5 mm


Week 8

1,5 cm


Week 9

2,6 cm


Week 10

2,8-3,1 cm


Week 11

3,7-4,1 cm


Week 12

5-5,5 cm


Week 13

6-7 cm


Week 14

7-8 cm


Week 15

9,5-10 cm


Week 16

10,8-11,6 cm


Week 17

11-12 cm


Week 18

12,5-14 cm


Week 19

15 cm


Week 20

16-20 cm


Week 21

26,7 cm


Week 22

28 cm


Week 23

28-30 cm


Week 24

30-31 cm


Week 25

34-35 cm


Week 26

35-36 cm


Week 27

36-36,6 cm


Week 28

37-37,2 cm


Week 29

38,7 cm


Week 30

40 cm


Week 31

41,5-41,8 cm


Week 32

42,7 cm


Week 33

43,5-43,8 cm


Week 34

45 cm


Week 35

46 cm


Week 36

47 cm


Week 37

48 cm


Week 38

49 cm


Week 39

50 cm


Week 40

51 cm

Pregnancy is a very beautiful and exciting time for expectant mothers and of course also for expectant fathers. Each week holds new surprises in store for you. Our HiPP Pregnancy Calendar provides you with an overview of the most important events during the 40 weeks of pregnancy. Find out more about each individual week:

  • How big is my baby?
  • What developmental leaps is my baby going through?
  • What signs and symptoms might I notice?
  • How will I feel as an expectant mother?

The HiPP Pregnancy Calendar addresses various issues you might be experiencing. Lots of useful tips and explanations support you and help you to understand what happens in your body when you are pregnant.

How to count your pregnancy weeks

A pregnancy usually lasts 40 weeks. Counting of your pregnancy starts on the first day of your last period. This means that in the first and second week of pregnancy you are actually not yet pregnant. It’s in week three that you ovulate and the egg is fertilised. Then, 9 months later, your baby is born.

You’ll quickly become familiar with how the progress of your pregnancy is counted (e.g. week 4+3). It’s always measured to the exact day: on average, there are 280 days or 40 weeks between the first day of your last period and the birth of your child.  The progress of your pregnancy is counted in weeks and then days, so the numbers 1 to 6 behind the plus sign represent the days.

Taking our previous example “week 4+3”: You count the full weeks plus the days of the next week, meaning that you are 4 weeks and 3 days pregnant. You can also say you are in week 5 of your pregnancy.

Let’s say your last period began on a Thursday. Being 4+3 weeks pregnant means that it’s 4 weeks after the first day of your last period plus Friday (+1), Saturday (+2), Sunday (+3). 

Pregnancy trimesters

Once the fertilised egg successfully implants in the uterus, your baby will develop rapidly. This developmental journey during pregnancy can be divided into 3 important stages, which last approx. 3 months each – the so-called trimesters. The third trimester is usually somewhat longer and marks the final developmental spurt of your baby before birth.

Use our HiPP Pregnancy Calendar to track your pregnancy week by week. Our HiPP Parents‘ Letters, which we’ll send you on a regular basis, will also provide you with lots of information and nutritional tips throughout your pregnancy.