The influence of pregnancy on the long-term renal prognosis of IgA nephropathy.

The effect of pregnancy on long-term renal prognosis in women with IgA nephropathy is disputed. The clinical courses of 71 patients with biopsy proven IgA nephropathy were followed for 5 years. Thirty-six patients became pregnant during the first 2 years of follow-up (P), the remaining 35 never conceived (non-P). The pathology in preconception renal biopsy was similar to that of the women who never became pregnant. Glomerular filtration rate (GFR) was measured yearly as the 24 hour-clearance of creatinine and was compared between the two groups. Initial clinical data of the P and non-P were: average age 25 +/- 3: 25 +/- 3 (yrs); serum creatinine 0.8 +/- 0.2: 0.7 +/- 0.2 (mg/dl); GFR 83 +/- 15: 87 +/- 15 (ml/min); blood pressure 119 +/- 10/74 +/- 9: 121 +/- 17/71 +/- 8 (mmHg); proteinuria 0.6 +/- 0.4: 0.9 +/- 0.6 (g/day). There were no significant differences between the two groups. Average initial (83 +/- 15: 87 +/- 15) and final (69 +/- 28: 69 +/- 24) GFRs were comparable. In 80% of P and 74% of non-P patients, the GFR decrement was 25% or less at five years. Four of the P and two of the non-P progressed to end-stage renal failure and required hemodialysis. No adverse influence of gestation on the natural course of IgA nephropathy was detected.