John C. Otto, who first described hemophilia as a separate entity, was born in 1774 near Woodburg, New Jersey, the son of a doctor. His grandfather came from Germany in 1752 and served as a military doctor on the American side during the Revolutionary War.
John C. Otto studied at the College of New Jersey (Princeton) and passed his exams there. In 1796 he received his doctorate at the University of Pennsylvania. In 1813 he succeeded his teacher Dr. Rush and became a doctor at the Pennsylvania Hospital. He earned great merits in the fight against epidemics. In 1803, he described all the clinical symptoms of hemophilia, recognized its heredity, described that only men suffered from it and recognized the role of women as conductors.