Increased Nuchal Translucency in Fetuses With a Crown-Rump Length of < 45 mm: Clinical Outcomes and Diagnostic Implications

NT measurement in fetuses with CRL < 45 mm provides clinically relevant prognostic information. Elevated NT in this early gestational window is significantly associated with chromosomal anomalies, structural defects, and poor pregnancy outcomes. Reliance on cell-free DNA screening for aneuploidy alone in this cohort may miss a substantial proportion of abnormal cases. Early NT assessment should prompt comprehensive diagnostic evaluation and genetic counseling, even when the CRL is below 45 mm.