The effect of oral contraceptive pills and the natural menstrual cYCLe on arterial stiffness and hemodynamICs (CYCLIC)

Over 100 million women currently use oral contraceptive pills (OCPs) worldwide. However, little is known about the effects of OCPs on arterial stiffness and hemodynamics. Furthermore, whether arterial stiffness and hemodynamics vary throughout the natural menstrual cycle remains controversial. Herein, we estimated the effect of the natural menstrual cycle and OCP use on arterial stiffness and hemodynamics.

Healthy, nonsmoking women, aged 18-30 years, were recruited if they had regular menstrual cycles and never used OCPs (OCP nonuser group), or were using low-dose OCPs for at least 6 months (OCP user group). Using applanation tonometry, three assessments of arterial stiffness and central and peripheral hemodynamics were performed in a randomized order: during the early follicular (days 3-6), late follicular (days 14-16), and luteal (days 22-26) phases. Within group and between group comparisons were performed using general linear models.

Sixty women (21.7 ± 2.8 years) were recruited. Compared with OCP nonusers, OCP users had significantly increased aortic and peripheral SBPs during the active OCP use, but not during the inert tablet phase. No differences in arterial stiffness were noted.

OCP use was associated with significant increases in aortic and peripheral blood pressures, but not with increased arterial stiffness. Given the widespread OCP use, future longitudinal studies are needed to confirm our findings and assess the long-term effect of OCPs on arterial stiffness and hemodynamics.