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Health Sciences Authority
Dear Healthcare Professional Letters

Update on risk of thromboembolism associated with combined oral contraceptives

Audiences

Healthcare professional

Product type

Therapeutic Products

26 May 2014

This article has been migrated from an earlier version of the site and may display formatting inconsistencies.

HSA would like to update healthcare professionals on the outcome of its review on the risk of thromboembolism associated with combined oral contraceptives (COCs). Although venous thromboembolism (VTE), which includes deep vein thrombosis and pulmonary embolism, is a known potential risk with the use of COCs, current evidence showed that the small absolute risk of VTE associated with COCs may differ depending on the type of progesterone present in the preparation. Based on scientific evidence to date, COCs containing levonorgestrel, norethisterone and norgestimate have the lowest VTE risk. COCs are also associated with an increased risk of arterial thromboembolism (ATE) but there is insufficient evidence to demonstrate if the ATE risk varies between different COCs. Healthcare professionals should take into consideration the latest evidence on the risk of thromboembolism associated with COCs when discussing the most suitable type of contraceptive for their patient. Careful consideration should be given to the woman’s risk factors for thromboembolism and these risk factors should be reassessed regularly. The risk of thromboembolism with a COC is higher during the first year of use, and when re-starting use after a break of 4 or more weeks. Please refer to the letter for more details.

Only abstracts of the Dear Healthcare Professional Letters (DHCPL) are provided on this website. Details of these letters can be found in the MOH Alert System, which is accessible via the Health Professionals Portal (HPP), a one-stop portal for all healthcare professionals in Singapore. Dentists, medical doctors and pharmacists may access HPP at https://hpp.moh.gov.sg (opens in new tab) and follow the procedures below to access the MOH Alert system.

Step 1: Select your profession under ‘For Healthcare Professionals’.

Step 2: Click on ‘Useful links’.

Step 3: Click on ‘MOH Alert’ and log in via Singpass.

Step 4: Click on ‘Drug Alerts’ or ‘Med Device Alerts’ to view the DHCPLs.