Human chorionic gonadotropin, commonly known as HCG, is a hormone produced by the placenta during pregnancy. It is used in pregnancy tests to confirm pregnancy, and also for fertility treatments. However, there are several other names or synonyms for HCG. Some of the commonly used synonyms include chorionic gonadotropin, chorionic gonadotrophin, beta-HCG, and luteinizing hormone. Other synonyms for HCG include human chorionic gonadotrophin, human chorionic gonadotropine, pregnancy hormone, and gonadotropin. These synonyms are often used interchangeably and refer to the same hormone produced during pregnancy.