ASUM would like to draw your attention to recent research conducted by the University of London and the Katholieke Universiteit Leuven, Belgium, published in the November 2011 issue of Ultrasound in Obstetrics and Gynaecology.The studies suggest that given inter‐observer variability in ultrasound measurements and the significant variation in early embryonic growth, a more conservative approach to the diagnosis of early pregnancy loss is warranted.The recommendation which has been temporarily endorsed by the RCOG suggests a mean sac diameter (MSD) cut off > 25 mm and a crown rump length (CRL) cut off> 7 mm be introduced to minimise the risk of a false positive diagnosis of miscarriage.While this research awaits confirmation from other centres ASUM suggests interim caution and highlights the importance of transvaginal confirmation of early pregnancy failure.It should also be noted that many other factors are used when assessing early pregnancy failure, including the presence of a yolk sac, shape of the gestation sac, position within the uterine cavity or cervix, progress from a previous scan and correlation with known gestational age especially in IVF pregnancies.