The use of a combined hormonal contraceptive (CHC) increases the risk of venous thromboembolism (VTE) compared to non-use. When prescribing a CHC, the current, individual risk factors of the individual female and the risk of the CHC concerned must be taken into consideration. The sharpest increase in risk of VTE occurs in the very first year of use, particularly during the first 3 months.
Combined hormonal contraceptives (CHC) and thromboembolic events
Incident data |
Description |
|---|---|
Case 1 Age group: between 15 and 20 years Sex: female Active substances: drospirenone/ethinylestradiol Indication: hormonal contraception ADR: pulmonary embolism Outcome: recovering |
Four months after starting oral contraception, the patient experienced pain in the lower left costal arch and shoulder related to respiration, which was exacerbated on lying down, with no fever or coughing. A chest X-ray showed pulmonary embolisms and suspected infarction pneumonia. No indication of right ventricular overload. The young woman had no risk factors for pulmonary embolism: non-smoker, no lengthy immobilisation/travel, no history of thrombosis/embolism, no known malignancy or other relevant pre-existing disease. After starting treatment with a direct oral anticoagulant, the patient was discharged home in an improved condition. |
Case 2 Age group: between 30 and 35 years Sex: female Active substances: chlormadinone acetate/ethinylestradiol Indication: oral contraception ADR: deep vein thromboses, central pulmonary embolism Outcome: fatal |
The patient died unexpectedly approximately one month after starting to take the combined oral contraceptive. The autopsy found deep vein thromboses in both lower extremities and a massive pulmonary embolism. The patient was a heavy smoker, obese (BMI > 30) and had a family history of deep vein thrombosis (paternal). |
Summary and recommendation
The use of a combined hormonal contraceptive (CHC) increases the risk of venous thromboembolism (VTE) compared to non-use. In individual females, the presence of other risk factors for VTE such as obesity, positive family history, smoking and increasing age must be taken into consideration. The risk of VTE also depends on the type of progestogen component in the CHC concerned: medicinal products containing levonorgestrel, norgestimate or norethisterone are associated with the lowest risk of VTE. The sharpest increase in risk of a VTE occurs in the very first year of use, particularly during the first 3 months.
When prescribing a CHC, the current, individual risk factors of the individual female and the risk of the CHC concerned must be taken into consideration. Possible symptoms of VTE must be explained to patients, and they should also be informed of the importance of seeking medical advice/treatment quickly if symptoms occur.
Healthcare professionals are requested to report serious and/or previously unknown adverse drug reactions to Swissmedic. Please use the Electronic Vigilance Reporting Portal “ElViS” for this purpose.
Electronic reports via the ElVis portal