Background: Oral contraceptives (OC) are among the most frequently used drugs in the world. We describe the population effects of current and long-term OC exposure on carotid-femoral pulse wave velocity (PWV).

Methods: The Asklepios study is a representative sample (n=2524, aged 35–55 years, 1301 women) from the Belgian general population, free from overt cardiovascular disease. The subjects were extensively screened; carotid-femoral PWV was measured using Doppler echography.

Results: Of 1301 women (median age 45.7 years), 27.4% were actively taking OC. However, past use of OC is far more prevalent with 81% having taken OC (median exposure 13 years).

Age-adjusted PWV was higher in women currently taking OC: 6.75 versus 6.55 m/s (difference 0.19±0.09 m/s; p=0.034). However, current OC users also had higher blood pressures (BP): systolic +4.4±0.9 mmHg, p<0.001; diastolic +2.3±0.6 mmHg, p<0.001. After adjustment for BP, the difference in PWV between current OC users and non-users became non-significant: 6.60 versus 6.62 m/s (difference 0.02±0.09 m/s; p=0.814). Duration of OC use, in contrast, remained a significant determinant of PWV, even after adjustment for age, BP, lipids, body size, heart rate, drug therapy (lipid-lowering, antihypertensive), glycemic status and smoking: F=6.1; p=0.013. Per 10 years of OC exposure PWV increased by 0.10 m/s (0.02–0.18; p=0.013).

Interpretation: Use of OC is associated with increased vascular stiffness. Current use is associated with increased PWV because OC’s increase BP, long-term use (probably through structural remodelling of the vessels) is an independent determinant of PWV, increasing PWV by 0.1 m/s per 10 years of exposure.