Fontanella F, Groen H, Duin LK, et al. - Researchers aimed at constructing reference values for fetal urinary bladder distension in pregnancy and using Z‐scores as a diagnostic tool to distinguish posterior urethral valves (PUV) from urethral atresia (UA). 3D ultrasound volumes in 225 pregnant women between 15 and 35 weeks of gestation were used to determine nomograms of fetal urinary bladder distension. They retrieved a total of 1,238 measurements of the urinary bladder. Thereafter, calculation of Z‐scores, derived from fetal nomograms, was done in 106 cases with suspected lower urinary tract obstruction (LUTO) (including 76 cases with PUV (72%), 22 cases with UA (21%), 4 with urethral stenosis (4%) cases and 4 with Megacystis‐Microcolon‐Intestinal Hypoperistalsis syndrome (MMIH, 4%). Significantly lower longitudinal bladder diameter Z‐score was recorded for fetuses with PUV compared with those with UA. They identified Z‐scores of LBD as reliable in distinguishing fetuses with LUTO caused by PUV from those with other subtypes of LUTO.