This paper uses the Millennium Cohort Study to look at ethnic differences in birth outcomes for a cohort of English children born in 2000 and 2001. There is an increasingly large literature showing that longer gestation and higher birthweight are positively associated with cognitive and non-cognitive outcomes later in life, so understanding sources of ethnic differences in these outcomes and identifying factors that may influence birth outcomes has a lot of potential policy interest. This paper shows that even after controlling for background characteristics in a number of ways, there still remain unexplained differences in both gestation and birthweight outcomes across broad ethnic groups. It also suggests, however, that there may be potential policy levers that could be used to narrow this ethnic gap in birth outcomes, such as reducing the proportion of underweight Asian mothers and overweight Black mothers and increasing ethnic minority attendance at antenatal classes.