Now days doctors prescribes many routine pathological tests in pregnancy in which blood and urine tests are very common. Protein in urine test is generally performed to check any kind of infection in body.
In normal health there should be no protein cells in urine. If there are protein cells found in urine test then there must be some health problem like infection in urinary track, some problem in kidney or you have developed preeclampsia or diabetes. In this condition your doctor will give you treatment and can prescribe some more pathological test.
If some has protein cells found in urine during pregnancy then she must consult a good doctor or hospital and take proper treatment because this can cause serious problem.