ABSTRACT
Prenatal exposure to ultrasound is not associated with adverse influence on school performance, physical, or neurologic function. Ultrasound should be performed by trained and experienced professionals, with continuing education and ongoing quality-monitoring programs. The main concern about the safety of ultrasound is based on tissue temperature elevation from energy transfer and its possible effect of cavitations, or the formation of microbubbles in the tissues exposed to ultrasound waves. Precise estimation of gestational age is extremely important for optimal obstetric care, including evaluation of fetal growth, interpretation of maternal screening markers, choosing the appropriate gestational age to perform interventions, and management of preterm and late-term pregnancies. Diagnostic criteria for the diagnosis of nonviable pregnancy in the first trimester is a subject that has undergone recent revision. The potential benefit of a third-trimester ultrasound examination greatly depends on the quality of prior ultrasounds and maternal indications. Placenta accreta spectrum represents abnormal adherence of the placenta to the myometrium.
