Background
Vitamin D deficiency in pregnancy is associated with adverse events such as pre‐eclampsia, primary caesarean section and vitamin D deficiency of the newborn. Vitamin D screening in pregnancy is not universal.

Aims
To evaluate the vitamin D status of pregnant women at our institution and assess the sensitivity of the current risk‐based screening guideline.

Methods
A prospective audit of vitamin D levels of all women presenting for their first antenatal booking visit during 3 four‐week periods (in 2009–2010) was conducted at the Women’s and Children’s Hospital, South Australia. The main outcome measure was 25‐hydroxyvitamin D3 levels. Information was also collected on body mass index, self‐reported ethnicity and whether or not vitamin D testing was indicated based on the hospital guidelines.

Results
Four hundred and seventy‐two women consented to inclusion in the audit. 67.4% (318/472) were ‘low‐risk’ according to the hospital guidelines for vitamin D screening. 46.2% of these women and 78.6% of ‘high‐risk’ women were vitamin D deficient (<60 nmol/L). Mean vitamin D levels were 62.7 ± 22.0 and 43.4 ± 26.3 nmol/L for low‐ and high‐risk women, respectively. 54.9% (147/268) of women who were found to be vitamin D deficient were classified as ‘low‐risk’ giving a sensitivity of 45% for the current risk‐based screening guideline. Conclusions Based on current normal ranges for vitamin D, risk‐based screening criteria for vitamin D deficiency in pregnancy fails to detect over half of vitamin D deficient women at our institution. Current South Australian guidelines should be amended in favour of universal screening of vitamin D for all pregnant patients at their booking visit.