The Kleihauer-Betke (KB) test is the standard method for quantitating fetal-maternal hemorrhage in maternal care. The critical component of the KB test is the counting of fetal and maternal red blood cells (RBC). However, manual counting still the dominant clinical method for KB test. Manual RBC counting takes ~20 minutes. In a standard procedure, a lab technologist, looking through the eyepieces of a microscope, manually counts about 2,000 RBC and calculates the fetal-maternal RBC ratio.