A study to determine if oral contraceptives (OC) impact cardiovascular disease (CVD) and all-cause death found that they not only did not increase risk, but may have a net benefit, which becomes more apparent the longer they are used.

“Women with oral contraceptive use throughout their reproductive life span may have a previously unrecognized protective factor for all‐cause death over time,” wrote the authors of the analysis, which looked at 161,017 women in the UK Biobank Cohort Study.

Previous studies on the risk of OC and CVD or death have been inconsistent, ranging from significant risk to none at all. The latest study, from the Journal of the American Heart Association, found a 9 percent lower risk of CVD events and 8 percent reduction in all-cause death. And those benefits appeared improve over time.

“Compared with the OC never users, individuals with a duration of OC use for >5 years were significantly associated with lower risks of all‐cause death, CVD events, CHD, and HF in the multivariable‐adjusted models, and those with a duration of OC use of 1 to 5 years were significantly associated with lower risks of CHD (P for trend<0.05),” they wrote.

The authors note that one of the limitations of their study is that the UK Biobank did not have detailed information on the formulation or dose of the contraceptives being used, making it difficult to evaluate dosage impact.