Successful pregnancy outcome is an uncommon occurrence in women requiring chronic dialytic treatment, and the most adequate dialysis therapy in the management of these pregnant patients has not been established. During the period 1988-1995, we studied the outcome of 17 pregnancies in dialyzed females, with an average age of 28.2 +/- 5.9 years (range: 18-38 years). Seven women had adequate urine volume (>800 ml/24 h). Five patients started dialysis after conception and the remaining 12 pregnancies were diagnosed after 6-72 months on dialysis. Fourteen women were maintained on hemodialysis (HD) and 3 on continuous ambulatory peritoneal dialysis (CAPD). The HD schedule was increased to 3 h 5-6 times weekly, and CAPD was increased to six 2-liter exchanges/day. Mean serum urea was 78.6 +/- 27.4 mg/dl (range 45-110); serum creatinine was 6.5 +/- 3.7 mg/dl (3.3-9.8 mg/dl); and hematocrit was 28.9 +/- 3.3 vol% (22-35 vol%). Anemia was partially controlled with rHuEpo in 8 patients. Significant problems were polyhydramnios in 7 cases (5 HD/2 CAPD), oligohydramnios in 1 (HD), gestational diabetes in 2 (CAPD), premature labor with spontaneous abortion at the 19th, 22nd and 28th weeks of gestation (2 HD/1 CAPD), hypertension in 8 (7 HD/1 CAPD), and sterile eosinophilic peritonitis in 1 case (CAPD). Mean gestational age at delivery in 14 successful pregnancies (12 HD/2 CAPD) was 32.3 +/- 2.6 weeks (27-36 weeks) and mean baby weight was 1,400.7 +/- 579.1 g (range 720-2,650 g). No congenital fetal abnormality was observed. Respiratory distress was observed in 6 infants, with 2 deaths (1 HD/1 CAPD) in the first week after delivery. In this study, successful pregnancies were reported in 70.6% of dialyzed women with uremia, with hemodialysis having a rate of fetal survival of 78.6% and CAPD with 33.3%.