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First-trimester obstetric ultrasound

First-trimester obstetric ultrasound (also called dating ultrasound) is used to more accurately determine the fetus’ gestational age (number of weeks of pregnancy). The ultrasound is done between the seventh and ninth week of gestation. This procedure can also confirm the number of fetuses, the death of a fetus or an ectopic pregnancy.

Other examination available: Obstetric and nuchal ultrasound

Preparing for the examination

To properly prepare for your first-trimester obstetric ultrasound, it is important to drink two 8-ounce glasses of water (500 mL) one hour before the examination and not urinate.

May I be accompanied by someone for my appointment?

Even during the pandemic, a person of your choice can accompany you during this exam. If you come accompanied, be informed that this person will have to answer the same screening questionnaire as you will have to, and access could be refused. 

A medical prescription is required to perform this examination.

The costs of this examination are covered by the Régie de l'assurance maladie du Québec (RAMQ) when prescribed by a physician*.

If your health care professional has requested this test or you have any questions, feel free to contact us at 1 833 590-2715.