Gross hematuria in the first month of life is a rare occurrence. Thirty-five patients with gross hematuria were admitted to Children's Memorial Hospital from 1950 to 1967. The causes included renal vein thrombosis; polycystic disease of the kidney; obstructive uropathy; sponge kidney; and Wilms tumor.
Emanuel B, Aronson N. Neonatal Hematuria. Am J Dis Child. 1974;128(2):204–206. doi:10.1001/archpedi.1974.02110270078015