CONTEXT: Depomedroxyprogesterone acetate (DMPA) (Depo Provera) is a long-acting contraceptive popular in the United Kingdom, particularly among young women. In the United States, use of DMPA has been instrumental in reducing teenage pregnancy rates. Evidence for a detrimental effect of DMPA on bone mineral density led to advice from drug regulatory authorities in the United Kingdom and the United States, recommending caution in prescribing DMPA, particularly for young people. OBJECTIVE: The study was conducted to explore changes in practice in response to prescribing advice about DMPA among primary care doctors and nurses working in the UK. METHODS: A self-completed questionnaire sent to 420 primary care health professionals. RESULTS: In response to the advice, 16% of practitioners would deter all women, and one third would deter young women, from using DMPA. One in five practitioners would limit use of DMPA to 2 years. Fewer than one in 10 would suggest contraceptive implants as an alternative contraceptive. CONCLUSIONS: The response of primary care professionals in their prescribing advice about DMPA risks increasing rates of unintended pregnancy in the UK, particularly among teenagers. The findings demonstrate an urgent need for a clear, balanced approach to advising health professionals on how to respond to new findings about adverse effects of contraceptives.