Vitamin D status of Asian mothers in Cardiff was investigated during early pregnancy and at the time of the birth of their babies, using serum parathyroid hormone (PTH). Median values in Asian (n 32) and Caucasian (n 63) mothers in early pregnancy were 1.56 and 0.81 pmol/l respectively. PTH levels from a separate sample of nineteen Asian and twenty-five Caucasian mothers at the time of birth were 3.0 and 2.20 pmol/l respectively. Altogether twelve Asian and two Caucasian women had elevated PTH. All Asian women who had high PTH values also had a very low serum 25-hydroxycholecalciferol level (25OHD). All samples were taken from women with no significant medical history and normal obstetric history. These findings suggest that subclinical vitamin D deficiency is still a cause for concern in Asian women. More active measures need to be taken to implement current recommendations to improve their vitamin D intake in pregnancy.