Pregnancy calendar: week by week

Choose your week of pregnancy – or let it be derived from your due date. Each week shows your baby’s development, common symptoms and the examinations scheduled for that stage.

The current week is then derived from it.

All 40 weeks at a glance

Week Size Weight Roughly Due this week
4+0 bis 4+6 about 1 mm under 1 g the size of a poppy seed None yet. An ultrasound would tell you little at this point – the gestational sac is only visible from about 5+0.
5+0 bis 5+6 about 2 mm under 1 g the size of a sesame seed Ultrasound shows the gestational sac; the embryo usually not yet.
6+0 bis 6+6 about 4 mm under 1 g the size of a lentil A first ultrasound is possible – heart activity, position of the gestational sac and the number of embryos.
7+0 bis 7+6 about 1 cm (crown-rump) around 1 g the size of a blueberry From now on the crown-rump length can be measured – the most accurate dating of the whole pregnancy.
8+0 bis 8+6 about 1.6 cm around 1 g the size of a raspberry First Eltern-Kind-Pass ultrasound, scheduled between 8+0 and 16+0.
9+0 bis 9+6 about 2.3 cm around 2 g the size of a grape Blood tests of the first examination: blood group, antibody screen, full blood count, rubella, toxoplasmosis, syphilis and, after counselling, HIV.
10+0 bis 10+6 about 3.1 cm around 4 g the size of a strawberry From 10+0 a non-invasive prenatal test (NIPT) from maternal blood is possible.
11+0 bis 11+6 about 4.1 cm around 7 g the size of a fig From 11+0 nuchal translucency can be measured, often as part of the combined test together with a blood sample. The window ends at 13+6.
12+0 bis 12+6 about 5.4 cm around 14 g the size of a lime Since October 2026 the window for the first Eltern-Kind-Pass ultrasound runs to 16+0.
13+0 bis 13+6 about 7.4 cm around 23 g the size of a lemon No fixed examination scheduled. From 14+0 a general medical examination is part of the extended Austrian programme.
14+0 bis 14+6 about 8.7 cm around 43 g the size of an apple Window for the general practice examination, the health conversation and the first midwife consultation (14th to 20th week).
15+0 bis 15+6 about 10.1 cm around 70 g the size of an avocado No fixed examination scheduled.
16+0 bis 16+6 about 11.6 cm around 100 g the size of a pear Latest date for the first Mutter-Kind-Pass examination and for the first ultrasound.
17+0 bis 17+6 about 13 cm around 140 g the size of a sweet potato No fixed examination; the window for the second Mutter-Kind-Pass examination opens at 18+0.
18+0 bis 18+6 about 14.2 cm around 190 g the size of a pepper Start of the window for the second examination and the anomaly scan (18th to 22nd week).
19+0 bis 19+6 about 15.3 cm around 240 g the size of a mango Core time for the anomaly scan.
20+0 bis 20+6 about 25.6 cm (crown to heel from now on) around 300 g as long as a banana End of the window for the midwife consultation, the health conversation and the general practice examination.
21+0 bis 21+6 about 26.7 cm around 360 g as long as a carrot Last weeks of the window for the second examination and the anomaly scan.
22+0 bis 22+6 about 27.8 cm around 430 g as long as a courgette No fixed examination scheduled.
23+0 bis 23+6 about 28.9 cm around 500 g as long as a large mango No fixed examination scheduled.
24+0 bis 24+6 about 30 cm around 600 g as long as a corn cob Start of the window for the third examination with the glucose tolerance test (24th to 28th week) and for the second midwife consultation (24th to 34th week).
25+0 bis 25+6 about 34.6 cm around 660 g as long as a cauliflower Third Mutter-Kind-Pass examination: second major blood test, hepatitis B, oral glucose tolerance test.
26+0 bis 26+6 about 35.6 cm around 760 g as long as a lettuce Core time for the glucose tolerance test.
27+0 bis 27+6 about 36.6 cm around 875 g as long as a Chinese cabbage End of the window for the third examination.
28+0 bis 28+6 about 37.6 cm around 1,000 g as heavy as a pineapple No fixed examination; from now on closer monitoring in higher-risk pregnancies.
29+0 bis 29+6 about 38.6 cm around 1,150 g as heavy as a coconut Start of the window for the fourth examination and the third ultrasound (30th to 34th week).
30+0 bis 30+6 about 40 cm around 1,320 g as heavy as a large courgette Fourth Mutter-Kind-Pass examination and third ultrasound.
31+0 bis 31+6 about 41 cm around 1,500 g as heavy as a pumpkin Core time for the fourth examination.
32+0 bis 32+6 about 42.4 cm around 1,700 g as heavy as a honeydew melon No additional examination.
33+0 bis 33+6 about 43.7 cm around 1,920 g as heavy as a pineapple Last opportunity for the fourth examination within the window.
34+0 bis 34+6 about 45 cm around 2,150 g as heavy as a cantaloupe melon Last week for the second midwife consultation; from 35+0 the window opens for the fifth examination and the fourth ultrasound (35th to 38th week).
35+0 bis 35+6 about 46.2 cm around 2,380 g as heavy as a honeydew melon Fifth Mutter-Kind-Pass examination, fourth ultrasound, swab for group B streptococcus.
36+0 bis 36+6 about 47.4 cm around 2,620 g as heavy as a romaine lettuce Core time for the fifth examination.
37+0 bis 37+6 about 48.6 cm around 2,860 g as heavy as a bunch of chard Fifth examination, if it has not yet taken place.
38+0 bis 38+6 about 49.8 cm around 3,080 g as heavy as a pumpkin Final date for the fifth Mutter-Kind-Pass examination.
39+0 bis 39+6 about 50.7 cm around 3,290 g as heavy as a small watermelon Check with CTG, every few days depending on how things go.
40+0 bis 40+6 about 51.2 cm around 3,460 g as heavy as a pumpkin Regular checks with CTG and ultrasound.
41+0 bis 41+6 about 51.7 cm around 3,600 g as heavy as a watermelon CTG and ultrasound every two to three days, with a check on amniotic fluid volume.
ab 42+0 about 51.5 cm around 3,690 g as heavy as a watermelon Monitoring daily to every second day.

Why “week 12” means two different things

In medical records a pregnancy is written as completed weeks plus days: 12+3 means twelve full weeks and three days. In everyday speech, however, “the twelfth week” means the week you are currently in – which in that notation is 11+0 to 11+6. The two differ by exactly one week, and that is the most common misunderstanding in any pregnancy.

Every week on this page carries both figures. Size and weight are reference values: healthy children differ considerably, and from around week 20 the measurement switches from crown-rump to full length – which is why the numbers jump there.

Sources

  1. Gesundheitsportal des Bundes: Eltern-Kind-Pass-Untersuchungen in der Schwangerschaft
  2. Hadlock FP u. a.: Estimation of fetal weight with the use of head, body, and femur measurements. American Journal of Obstetrics and Gynecology 151 (1985) 333–337
What this tool cannot do

It works with averages. Your body does not. The result is a starting point for a conversation, not a finding – and it cannot see what an examination would show.

Questions about your result? Arrange an appointment.