Background— Preeclampsia, a new-onset hypertensive disorder of pregnancy, is associated with lifetime cardiovascular disease risk, but less is known about risk after other pregnancy-related hypertension. Methods and Results— The Northern Finland Birth Cohort 1966 included all expected births from 1 year ( N =12 055 women). Blood pressure measurements and other prospective data were determined from prenatal care records and questionnaires for 10 314 women. Subsequent diagnoses were ascertained from Finnish registries (average follow-up, 39.4 years). Adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) estimate risks in hypertensive women compared with normotensive women. Hypertension during pregnancy was associated with increased risk of subsequent cardiovascular disease and arterial hypertension. Women with chronic hypertension and superimposed preeclampsia/eclampsia had high risk for future diseases. Gestational hypertension was associated with increased risk of ischemic heart disease (HR, 1.44 [95% CI, 1.24–1.68]), myocardial infarcts (HR, 1.75 [95% CI, 1.40–2.19]), myocardial infarct death (HR, 3.00 [95% CI, 1.98–4.55]), heart failure (HR, 1.78 [95% CI, 1.43–2.21]), ischemic stroke (HR, 1.59 [95% CI, 1.24–2.04]), kidney disease (HR, 1.91 [95% CI, 1.18–3.09]), and diabetes mellitus (HR, 1.52 [95% CI, 1.21–1.89]). Isolated systolic hypertension was associated with increased risk of myocardial infarct death (HR, 2.15 [95% CI, 1.35–3.41]), heart failure (HR, 1.43 [95% CI, 1.13–1.82]), and diabetes mellitus (HR, 1.42 [95% CI, 1.13–1.78]), whereas isolated diastolic hypertension was associated with increased risk of ischemic heart disease (HR, 1.26 [95% CI, 1.05–1.50]). Results were similar in nonsmoking women aged <35 years with normal weight and no diabetes mellitus during pregnancy. Conclusions— Elevated blood pressure during pregnancy, regardless of type and even without known risk factors, signals high risk of later cardiovascular disease, chronic kidney disease, and diabetes mellitus. Clinical monitoring, risk factor evaluation, and early intervention could benefit women with hypertension in pregnancy.