Risks of Combined Oral Contraceptives Revealed in New Study
Recent findings from a significant study presented at the European Stroke Organisation Conference (ESOC) 2025 highlight a concerning connection between combined oral contraceptives (OCs) and an increased risk of cryptogenic ischaemic stroke (CIS) in young women. This research indicates that the use of these contraceptives may elevate the risk by three times.
Cryptogenic ischaemic stroke, characterized by the lack of identifiable causes, represents a substantial portion of ischaemic strokes amongst the young, accounting for almost 40% of cases. Researchers have long known the prevalence of this condition, but risk factors specifically related to contraceptive use among women have received limited attention until now.
The Searching for Explanations for Cryptogenic Stroke in the Young (SECRETO) study recruited a total of 536 participants, comparing 268 women aged 18 to 49 suffering from CIS with an equal number of healthy controls. The study took place across 14 medical centers in Europe, emphasizing a robust and broad research environment. Notably, of these participants, 66 CIS patients were using combined OCs alongside 38 stroke-free controls.
Adjustments were made for various established risk factors including age, history of hypertension, smoking, migraine with aura, and abdominal obesity. The results revealed a striking adjusted odds ratio of 3.00 (95% CI: 1.61–5.57) associated with OC use. This finding suggests that the heightened risk of stroke linked with OCs might occur independently of other risk factors.
Insights from the Research Team
Dr. Mine Sezgin, the lead author from the Department of Neurology at Istanbul University, expressed the importance of these results. She noted, "The findings reinforce prior evidence linking oral contraceptives to stroke risk. We found it especially significant that the association persists even when accounting for established risk factors, indicating potential additional mechanisms, be they genetic or biological."
The majority of women involved in the study were using ethinylestradiol-based formulations, with a median dose of 20 micrograms. There were also instances of other estrogen types, including estradiol hemihydrate and estradiol valerate, adding depth to the investigation of OCs.
Dr. Sezgin elaborated, "To ensure clarity, we calculated the equivalent estrogen dose for every participant in the study. While these initial insights are invaluable, there's a pressing need for larger-scale studies to determine the variance in risk levels between different OC formulations. This knowledge could eventually lead to more personalized contraceptive choices for women as they navigate their health options."
Although the research advocates for continued exploration, it also emphasizes caution among healthcare providers when recommending combined OCs for young women, especially those possessing pre-existing vascular risk factors or a history of ischaemic stroke. Dr. Sezgin concluded with a call to action: "Our research should inspire a more thorough assessment of stroke risk in young women, particularly those presenting additional risk factors."
Future Directions in Research
In the wake of these findings, the research team aims to delve deeper into the biological and genetic mechanisms that may explain the correlation between combined OC usage and an increased risk of stroke. Understanding these underlying factors will be crucial in comprehending how hormonal contraceptives could independently heighten stroke risks.
Note to Editors: Coverage of this study must incorporate a reference to ESOC 2025.
About Dr. Mine Sezgin
Dr. Mine Sezgin is a dedicated neurologist and stroke researcher based at Istanbul University Faculty of Medicine. Her work primarily investigates sex-specific risk factors and aims at preventing strokes among young adults.
About the European Stroke Organisation (ESO)
The European Stroke Organisation is a premier association that encompasses stroke researchers, physicians, and lay organizations across Europe, established to combat the stroke burden through education and enhancing institutional processes. Founded in December 2007, ESO advocates for unified stroke management and strives to reduce the impact of strokes on a regional and global scale.
Frequently Asked Questions
What is the main finding of the study presented at ESOC 2025?
The study indicates a threefold increase in the risk of cryptogenic ischaemic stroke in young women who use combined oral contraceptives.
How many participants were involved in the SECRETO study?
The SECRETO study involved a total of 536 participants, with 268 women suffering from cryptogenic stroke and 268 healthy controls.
What were the characteristics of the oral contraceptives studied?
The study mainly focused on ethinylestradiol-based formulations with a median dose of 20 micrograms, among other estrogen types.
What advice do the researchers give regarding contraceptive prescriptions?
They advise clinicians to exercise caution in prescribing combined oral contraceptives to women with known vascular risk factors or a history of ischaemic strokes.
What future steps are planned by the research team?
The researchers plan to investigate the biological and genetic mechanisms that explain the association between combined OC use and stroke risk.
