Ramb - Janeiro

imões

and

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2017; 63(1):4-6

examination of euploid fetuses due to increased nuchal

translucency.

(

) In this regard, the findings of the re-

lated studies do not reflect the true performance of first-

-trimester ultrasonography for the screening of nonchro-

mosomal abnormalities. A multicenter clinical trial

conducted by Saltvedt et al. was designed to analyze the

sensitivity of morphological ultrasound examinations

performed during the first and second trimesters to iden-

tify fetal malformations. To do so, they randomized more

than 39,000 pregnant women to perform a single ultra-

sound during pregnancy, between weeks 12 and 14, or

between weeks 15 and 22. The authors found a detection

rate of 38% for the first group compared to 47% for the

second, but the difference was not significant.

(

)

ecommendation

Routine ultrasonography performed in the first trimester

of low-risk pregnancies allows a better calculation of ges-

tational age, preventing diagnosis of a later due date and

consequent iatrogenic preterm delivery. It also allows the

characterization of the number of fetuses and chorionic-

ity.

(

). This imaging modality also contributes to the

identification of aneuploidy and, increasingly, to the di-

agnosis of structural anomalies.

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