Preeclampsia is associated with later kidney disease. This study tested the hypothesis that the normal decline in renal function with age is more rapid in formerly preeclamptic women than in controls. Four groups were compared cross-sectionally: young women with a history of preeclampsia (n = 34), young controls (n = 12), middle-aged women with a history of preeclampsia (n = 22) and middle-aged controls (n = 29). We measured blood pressure (semi-automatic device), effective renal plasma flow (ERPF, para-aminohippurate clearance), glomerular filtration rate (GFR, creatinine clearance) and cardiac output (Doppler echocardiography). ERPF was lower in both young and middle-aged women with a history of preeclampsia relative to controls. The decrease in both GFR and ERPF with age was comparable in both groups. In conclusion, the lower renal function in middle-aged formerly preeclamptic women does not result from accelerated age-dependent renal function loss, but from an already reduced renal function relative to parous controls at young age.