Pregnancy is divided into 3 trimesters. The first 12 weeks are called the 1st trimester.

In the 1st trimester, the fetus's various organs develop. When we talk about early ultrasound, we mean examinations in the first 12 weeks of pregnancy. In most cases, we perform the examination with the ultrasound probe on the abdomen, but sometimes we have to use transvaginal ultrasound to get a better overview of the fetus. What can be seen on ultrasound in the 1st trimester? With early ultrasound we can:

• Confirm pregnancy
• Check the number of fetuses
• See that the fetus is inside the uterine cavity
• See cardiac activity
• Estimate gestation length

In case of multiples, or any discrepancies, we will refer to the Fetal Medicine department at Riks Hospitalet - Oslo University Hospital.

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Wondering how many weeks pregnant you are? Register the first day of your last period here.