Early Ultrasound Examination

Ultrasound technology in obstetrics is becoming increasingly useful. Traditionally, just one ultrasound examination used to be carried out in the pregnancy at around 20 weeks. This still remains important because it allows the morphological examination of the fetus, during which the various internal and external parts of the fetus can be viewed and abnormalities diagnosed.

However, there are a number of advantages to employing ultrasound earlier in the pregnancy. The primary purpose is to check the viability of a pregnancy when vaginal bleeding is present and to make sure that the fetus is properly located within the uterus if there is abdominal pain. Gestational age can be determined more closely, providing provide a more accurate expected delivery date for women whose menstrual cycles are irregular or who are uncertain about when they last menstruated. Early ultrasound examination also enables the diagnosis of twin pregnancies and determining whether one or two placentas are present. This information is important for the subsequent management of multiple pregnancies.

An obstetrical ultrasound between 12 and 14 weeks also permits measurement of nuchal transparency, the screening tool for trisomy 21. However, this measurement is not readily available everywhere in Quebec and must be carried out by people specially trained for this purpose.

With the constant improvement in ultrasound equipment, various severe abnormalities can also be viewed during an early ultrasound, such as anencephalia, omphalocele, enlarged bladder, etc.

It is therefore important to see your doctor before the 12th week of your pregnancy and discuss whether it would be appropriate for you to have an early obstetrical ultrasound examination.

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