Prenatal ultrasound examination is an important means for screening and evaluating fetal structures. With the improvement in resolution and the accumulation of evidence-based medicine，ultrasound indicators have evolved from empirical identification to refined management tools based on risk stratification. "Hard markers" serve as direct evidence of structural malformations and are clear indications for initiating invasive prenatal diagnosis and multidisciplinary treatment. "Soft markers"， on the other hand，represent minor ultrasound manifestations，and the interpretation of their clinical significance is highly dependent on whether they occur in isolation，the background risk of the mother，and the results of related molecular genetic testing.On entering the era of molecular medicine，with the widespread application of non-invasive prenatal screening，chromosomal microarray technology，and high-throughput sequencing technology，clinicians should understand and master how to construct an integrated diagnosis and treatment model of "image recognition-risk stratification-molecular diagnosis-prognosis assessment-individualized counseling"，and learn how to move from static image recognition to evidence-based quantification and from abnormal static records to systematic pathological reasoning.