性行為
Adultery (engaging in sexual intercourse with someone other than one's spouse) has been, and remains, a criminal offense in some jurisdictions. Sexual intercourse between unmarried partners and cohabitation of an unmarried couple are also illegal in some jurisdictions. Conversely, in other countries, marriage is not required, socially or legally, in order to have sexual intercourse or to procreate (for example, the majority of births are outside of marriage in countries such as Iceland, Norway, Sweden, Denmark, Bulgaria, Estonia, Slovenia, France, Belgium).