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.