and in the progression of chronic renal disorders.29-31 Alternatively, preeclampsia may exacerbate subclinical kidney disease that is present before pregnancy. This hypothesis is consistent with our previous finding that preeclampsia was associated with similar relative risks for receiving a diagnosis of a specific type of renal disease on renal biopsy and for undergoing a renal biopsy.5 The hypothesis is also consistent with our present finding that preeclampsia is associated with similar relative risks for the development of ESRD due to a specific cause and for the development of ESRD in general. However, our results were not
substantially changed after the exclusion of data from women who had kidney or urinary tract disease before pregnancy. A third possibility is that preeclampsia may cause later renal disease. The observation in other studies that 20 to 40% of women with preeclampsia have microalbuminuria 3 to 5 years after pregnancy, as compared with only 2% of women without preeclampsia,12,13 may be interpreted as supporting a causal association. However, it is also possible that the women with preeclampsia and subsequent microalbuminuria had unrecognized renal disease before pregnancy