The purpose of this study is to report short-term pregnancy outcome, subsequent pregnancy outcome, and remote prognosis (follow-up from 0.3 to 9.8 years) in 31 cases complicated by acute renal failure. Eighteen patients had "pure" preeclampsia and 12 patients (13 pregnancies) had chronic hypertension, parenchymal renal disease, or both before pregnancy. All patients had serial evaluation of renal function, urine microscopy, and electrolyte studies at the onset of acute renal failure and on follow-up. There were three immediate maternal deaths (two in the pure preeclampsia group and one in the other group). Nine patients (50%) in the "pure" group required dialysis during hospitalization and all 18 patients had acute tubular necrosis. Five patients (42%) in the other group required immediate dialysis and three patients had bilateral cortical necrosis. The majority of pregnancies in both groups were complicated by abruptio placentae and hemorrhage. All 16 surviving patients in the pure preeclampsia group had normal renal function on long-term follow-up (average 4.0 +/- 3.1 years). Conversely, nine of the 11 surviving patients in the second group required long-term dialysis on follow-up and four of them ultimately died of end-stage renal disease. We conclude that proper management of acute renal failure in patients with pure preeclampsia-eclampsia does not result in residual function impairment.