Renal Biopsy in Pregnancy: Risks, Benefits, Pathologic Findings, and Illustrative Examples

The use of renal biopsy during pregnancy remains controversial. While it is considered safe by some authors, a risk/benefit ratio must still be considered whenever the procedure is contemplated, weighing the risks to maternal health and ultimate pregnancy outcome. One must keep in mind potentiation of bleeding risk in a woman who is preeclamptic or who has uncontrolled hypertension. If the performance of a kidney biopsy is thought to result in a potential change in therapeutic management, it may be reasonable to perform this procedure. Preeclampsia is an important clinical concern but does not usually require biopsy for diagnosis. However, in some situations it may be important to distinguish preeclampsia from other clinicopathologic entities that can mimic or be superimposed upon it. The pathologic features of preeclampsia are well established, but they are not specific to preeclampsia and may even be seen during normal pregnancy.