Oral contraceptive use, iron stores and vascular endothelial function in healthy women

Abstract

Background: Increased iron stores are associated with greater cardiovascular risk in postmenopausal women. Oral contraceptive pill (OCP) use decreases the volume of menstrual blood loss and increases iron stores, but the link between OCP use, iron stores and cardiovascular risk in premenopausal women has not been characterized.

Study design: We conducted a cross-sectional study of 23 healthy OCP users to determine the association between type and duration of OCP exposure, iron stores, and vascular endothelial function [flow-mediated dilation (FMD) in the brachial artery].

Results: Median duration of OCP use was 45 months. FMD in the brachial artery was significantly associated with progestin type used (estranes/gonanes vs. drospirenone) and duration of OCP use (both p<.05) but not iron stores. In multivariate analysis, progestin type was the only independent predictor of FMD.

Conclusions: Use of OCP containing drospirenone was independently associated with greater FMD in the brachial artery and, thus, a potentially more favorable cardiovascular risk profile, when compared with use of OCP containing estranes/gonanes.

Fig. 1

Box plots showing the distribution of brachial artery flow-mediated dilation (FMD) values in subjects grouped by progestin type (estrane/gonane vs. drospirenone). Box plots indicate median value (within box), interquartile range (upper and lower limits of box), values adjacent to 1.5 × IQR (box whiskers) and if present, individual data points outside this range. The mean brachial artery FMD of subjects taking estranes/gonanes (1.5±2.8%, N= 15) was significantly lower than that of subjects taking drospirenone (5.6±4.4%, N= 7). * indicates p<0.05 vs. drospirenone group.