The U.S. women's teams compete in several international events each season, along with the Olympic Winter Games, which take place every four years. The International Ice Hockey Federation holds two major women's competitions each season — the Women's World Championship and the Under-18 Women's World Championship. In addition, the U.S Women's National Team faces off against Canada in the Rivalry series each year. The U.S. has won five of the previous seven IIHF Women’s World Championships. The U.S. Under-18 Women’s National Team has also claimed five of the last seven gold medals at the IIHF Under-18 Women’s World Championship.