Invasive assessment of fetal renal abnormalities: urinalysis, fetal blood sampling and biopsy.

There are a number of potential biochemical markers that may have some role in predicting renal function postnatally. These include urinary sodium, calcium and beta2-microglobulin. The latter may also be measured in fetal serum. However, the accuracy of these parameters at a point in time is far from perfect as urinary tract obstruction is a progressive disease which may be best defined by repeated observations throughout pregnancy. Copyright 2001 John Wiley & Sons, Ltd.