OBJECTIVE--To study the association between non-fasting serum triglyceride concentrations and mortality in women from coronary and cardiovascular disease and all causes. DESIGN--Follow up by ambulatory teams of men and women who underwent cardiovascular screening for a mean of 14.6 years. SETTING--National health screening service in Norway. SUBJECTS--25,058 men and 24,535 women aged 35-49 years. MAIN OUTCOME MEASURE--Predictive value of non-fasting serum triglyceride concentrations. RESULTS--At initial screening total serum cholesterol concentration, serum triglyceride concentration, blood pressure, height, and weight were measured, and self reported information about smoking habits, physical activity, and time since last meal were recorded. During subsequent follow up 108 women died from coronary heart disease, 238 from cardiovascular diseases, and 931 from all causes. In women mortality increased steadily with increasing triglyceride concentration for all three causes of death. With the proportional hazards model and adjustment for age, systolic blood pressure, total cholesterol concentration, time since last meal, and number of cigarettes a day the relative risk between triglyceride concentration > or = 3.5 mmol/l and < 1.5 mmol/l was 4.7 (95% confidence interval 2.5 to 8.9) for deaths from coronary heart disease, 3.0 (1.9 to 4.8) for deaths from cardiovascular disease, 2.3 (1.8 to 2.9) for total deaths in all women. CONCLUSIONS--A raised non-fasting concentration of triglycerides is an independent risk factor for mortality from coronary heart disease, cardiovascular disease, and any cause mortality among middle aged Norwegian women in contrast to what is seen in men.