Forced marriage and child marriage are prevalent in many parts of the world, especially in parts of Asia and Africa. A forced marriage is a marriage where one or both participants are married without their freely given consent; while a child marriage is a marriage where one or both parties are younger than 18. These types of marriages are associated with a higher rate of domestic violence, including marital rape. These forms of marriage are most common in traditional societies which have no laws against sexual violence in marriage, and where it is also very difficult to leave a marriage. Incidents taking place in some of these countries (such as Yemen) have received international attention. The World Health Organization states, under the rubric "Customary forms of sexual violence", (pp. 156):