... , doubling every 1.3 to 2 days. At the time of the last missed menstrual period, urine HCG levels are about 100mlU ... , 000 to 200, 000mlU/ml seen at the end of the first trimester. The presence of HCG soon after conception and its ... clinics, hospitals, and testing laboratories. Blue Cross currently offers in the following specialties: Fertility, Infectious Diseases, Sexually-Transmitted Diseases, and ...