A consensus statement from both headache and stroke experts suggests screening for and treatment of all traditional stroke risk factors in women with migraine but does not state that low-dose OC use is Hormonal Contraception and BP The impact of OC use on BP, an important stroke risk fac- tor, and other hemodynamic parameters is somewhat contro- versial. A study of BP and hemodynamic measurements in young women (mean age 20 years) in the United Kingdom (ENIGMA Study) showed that women using OCs had a mar- ginal but significantly higher systolic BP (mean 112 12 ver- sus 110 11 mmHg in nonusers; P=0.04) and an increased arterial pulse wave velocity, a measure of aortic stiffness232 ; however, in the multivariate model, mean arterial pressure, age, and heart rate were associated with arterial pulse wave velocity but not OC use.232 Several systematic reviews cover the topic of OC use and hypertension in women. Summarizing the data through 2005, one review estimated the odds of IS for women with hyperten- sion using OCs were 1.73 (95% CI, 0.83 3.60) and concluded that there was no synergistic increase in risk because the odds of stroke in normotensive women using OCs were similar.233 A systematic review of studies that examined BP after ini- tiation of OCs demonstrated mixed results from studies of follow-up BPs. Generally, the mean BPs were most often well below 140/90 mmHg. 