Oral contraceptive use and abnormal glucose regulation in Swedish middle aged women

To investigate the association between oral contraceptive (OC) use and abnormal glucose regulation in Swedish middle aged women.

A prospective population-based study including 4794 women, aged 36-56 at baseline. None had previously diagnosed diabetes. At both baseline and follow-up 8 years later, the women were examined by oral glucose tolerance test. Information regarding lifestyle factors and anthropometric measurements were collected.

At baseline, current use of OCs was associated with pre (Odds ratio, OR 4.1, 95%CI 2.2-7.8) but not with type 2 diabetes. The association to prediabetes was entirely linked to IGT (OR 7.1, 3.3-15.8) in current users of OCs and in former users (OR 2.1, 1.1-3.9). Women who used OC at baseline had a better cardiovascular disease risk profile; lower body mass index (BMI), more physically active and less smoking. At follow-up, the increased risk did not persist.

Current use of OC was associated with a four times increased risk of having prediabetes and seven times of having impaired glucose tolerance. No increased risk persisted at the follow-up, suggesting that the risk due to prior use of OC is decreasing with time. The healthier lifestyle in women who used OCs may have contributed to reduced long-term risk of prediabetes.