C Peptide is part of the molecule of Proinsulin, the insulin precursor molecule, that consists of three parts: C Peptide and two long strands of amino acids (called the alpha and beta chains) that later become linked together to form the insulin molecule. From every molecule of proinsulin, one molecule of insulin plus one molecule of C Peptide are produced. C peptide is released into the blood stream in equal amounts to insulin. A test of C peptide levels will show how much insulin the body is making. The ratio of C-peptide and Proinsulin in human serum is also very important in diagnosis and prognosis of various diseases like Polycystic Ovary Syndrome, Ovarian carcinoma, etc.
