A total of 1997 pregnant women were screened during their first antenatal visit for irregular antibodies for the prevention of haemolytic disease of the newborn. Patient sera were tested against a panel of group O screen cells including one with the expression of Miltenberger determinants GP.Mur. 17 women (0.85%) had irregular antibodies of which four were of potential clinical significance, including one with anti-D, two with anti-E and one with anti-D, anti-E and anti-G. Although antenatal antibody screening is mandatory in Western populations, our results suggest that this may not be necessary in the Chinese population except for those who are Rh D-negative or who have a history of haemolytic disease of the newborn.