Kidney Disease in Pregnancy

Abstract

Pregnancy-induced changes in renal hemodynamics play an important role in favorable maternal and fetal outcomes. Renal plasma flow and glomerular filtration rate (GFR) increase by approximately 50% in normal pregnancy, leading to a decrease in both blood urea nitrogen and serum creatinine when compared with prepregnancy levels. Hence, serum creatinine–based formulas are not accurate in calculating estimated GFR in pregnant patients. The most compelling risk for pregnant women with moderate to severe chronic kidney disease is the risk of rapid progression of underlying kidney disease; the mechanisms for such decline are yet to be elucidated. The rule of kidney disease not progressing when serum creatinine is less than 1.4 mg/dL does not apply to women with lupus nephritis. New-onset lupus is an indication for kidney biopsy during pregnancy because diffuse proliferative lupus nephritis requires prompt treatment and first-line treatments are teratogenic. Infertility is common in women on dialysis and is usually reversed after successful kidney transplantation. Pregnancy outcomes have improved over the years with increasing intensity of hemodialysis in end-stage kidney disease patients. Pregnancy post–kidney transplantation should be planned and teratogenic medications discontinued before conception. Key words: glomerular filtration rate, proliferative lupus nephritis, serum creatinine, pregnancy post–kidney transplantation, end-stage kidney disease, infertility, kidney biopsy