The use of bromocriptine for the suppression of postpartum lactation drew widespread attention to a potentially increased risk for cardiovascular and cerebrovascular adverse effects. To estimate the incidence of these events a follow-up study was prformed among 2,130 women of 15-44 years of age who were treated with a course of bromocriptine in 1990-1992. None of these women were admitted to the hospital for cardiovascular or cerebrovascular events. However, the incidence of pregnancy hypertensionand the use of cardiovascular drugs increased considerably in the last 2 months before delivery. Therefore, cardiovascular or cerebrovascular events can probably be explained by pre-existing morbidity rather than by the use of bromocriptine. We estimated, using a ‘worst-case’ analysis, that fewer than 2 Dutch women each year would develop serious cardiovascular or cerebrovascular events.