The 36-Week Anomaly Scan (2025)

Based on the landmark 2025 study by Syngelaki et al. a routine 36-week ultrasound is essential, as nearly 32% of all prenatally diagnosed anomalies are first detected at this stage. A dedicated third-trimester anatomical sweep catches late-evolving defects missed during standard mid-trimester screening.

​Key late-presenting anomalies include:

• ​Genitourinary & Cardiac: Hydronephrosis, duplex kidneys, and VSDs.

• ​Exclusively Late-Onset: Fetal ovarian cysts, achondroplasia, microcephaly, hematocolpos, and vein of Galen malformations.