The ISUOG Practice Guidelines on third-trimester obstetric ultrasound scan provide recommendations for the performance of this examination. The guidelines aim to ensure accurate assessment of fetal anomalies, growth, amniotic fluid volume, and fetal and uterine artery Doppler findings. They emphasize the importance of determining placental location, fetal presentation, and biometry, as well as evaluating for small-for-gestational age (SGA), large-for-gestational age (LGA), and macrosomia. The optimal gestational age for the scan is between 32 and 36 weeks, depending on the individual's risk level and clinical needs. The guidelines also address specific situations such as suspected vasa previa or low-lying placenta with a previous Cesarean section, where additional assessments are required. The guidelines recommend that third-trimester ultrasound scans should be performed in accordance with established techniques, including the use of real-time grayscale ultrasound, transabdominal and transvaginal transducers, and Doppler imaging. They emphasize the importance of assessing fetal wellbeing, including umbilical artery Doppler in high-risk pregnancies and additional Doppler parameters when indicated. The guidelines also address the assessment of placenta previa, placenta accreta spectrum, and vasa previa, with specific recommendations for the use of transvaginal ultrasound in suspected cases. The guidelines also provide recommendations for the assessment of fetal growth abnormalities, including SGA and LGA, and emphasize the importance of performing scans at 36 weeks rather than 32 weeks for improved accuracy. They also address the assessment of amniotic fluid volume, with recommendations for the use of amniotic fluid index (AFI) or deepest vertical pocket (DVP) measurements. The guidelines highlight the importance of identifying and managing conditions such as oligohydramnios and polyhydramnios, with specific recommendations for the use of ultrasound in diagnosing and managing these conditions. The guidelines also address the issue of perinatal mortality and emphasize the importance of accurate ultrasound assessment in predicting outcomes. They recommend that third-trimester ultrasound scans should be performed in accordance with established techniques and that healthcare professionals should balance the benefits of induction of labor for suspected macrosomia with the potential adverse effects of early-term delivery. The guidelines also emphasize the importance of multidisciplinary management for cases of placenta previa and placenta accreta spectrum, with recommendations for the use of MRI in certain situations. Overall, the guidelines aim to provide healthcare professionals with a consensus-based approach to the performance of third-trimester ultrasound scans, ensuring accurate assessment and improved outcomes for both mother and baby.The ISUOG Practice Guidelines on third-trimester obstetric ultrasound scan provide recommendations for the performance of this examination. The guidelines aim to ensure accurate assessment of fetal anomalies, growth, amniotic fluid volume, and fetal and uterine artery Doppler findings. They emphasize the importance of determining placental location, fetal presentation, and biometry, as well as evaluating for small-for-gestational age (SGA), large-for-gestational age (LGA), and macrosomia. The optimal gestational age for the scan is between 32 and 36 weeks, depending on the individual's risk level and clinical needs. The guidelines also address specific situations such as suspected vasa previa or low-lying placenta with a previous Cesarean section, where additional assessments are required. The guidelines recommend that third-trimester ultrasound scans should be performed in accordance with established techniques, including the use of real-time grayscale ultrasound, transabdominal and transvaginal transducers, and Doppler imaging. They emphasize the importance of assessing fetal wellbeing, including umbilical artery Doppler in high-risk pregnancies and additional Doppler parameters when indicated. The guidelines also address the assessment of placenta previa, placenta accreta spectrum, and vasa previa, with specific recommendations for the use of transvaginal ultrasound in suspected cases. The guidelines also provide recommendations for the assessment of fetal growth abnormalities, including SGA and LGA, and emphasize the importance of performing scans at 36 weeks rather than 32 weeks for improved accuracy. They also address the assessment of amniotic fluid volume, with recommendations for the use of amniotic fluid index (AFI) or deepest vertical pocket (DVP) measurements. The guidelines highlight the importance of identifying and managing conditions such as oligohydramnios and polyhydramnios, with specific recommendations for the use of ultrasound in diagnosing and managing these conditions. The guidelines also address the issue of perinatal mortality and emphasize the importance of accurate ultrasound assessment in predicting outcomes. They recommend that third-trimester ultrasound scans should be performed in accordance with established techniques and that healthcare professionals should balance the benefits of induction of labor for suspected macrosomia with the potential adverse effects of early-term delivery. The guidelines also emphasize the importance of multidisciplinary management for cases of placenta previa and placenta accreta spectrum, with recommendations for the use of MRI in certain situations. Overall, the guidelines aim to provide healthcare professionals with a consensus-based approach to the performance of third-trimester ultrasound scans, ensuring accurate assessment and improved outcomes for both mother and baby.