The incidence of nausea and vomiting-complicated pregnancy was determined in a district hospital in Hong Kong. Nausea was present in 11.4% and vomiting in 63.5% of pregnant women. Patients with vomiting complicating early pregnancy have a statistically significant higher incidence of antepartum haemorrhage of indeterminate origin. The incidences of medical diseases complicating pregnancy, other major antenatal complications, and the neonatal outcome were not different between vomiting and non-vomiting patients.