Infanticide (or infant homicide) is the intentional killing of infants or offspring. Now mostly illegal (apart from some countries[where?]), infanticide was a widespread practice throughout human history that was mainly used to dispose of unwanted children.[1]:61 Its main purposes saving resources from being spent on weak or disabled offspring. Unwanted infants were normally abandoned to die of exposure, but in some societies they were manually killed. Most Stone Age human societies routinely practiced infanticide, and estimates of children killed by infanticide in the Mesolithic and Neolithic eras vary from 15 to 50 percent. Infanticide continued to be common in most societies after the historical era began, including ancient Greece, ancient Rome, the Phoenicians, ancient China, ancient Japan, Aboriginal Australia, Native Americans, and Native Alaskans.

Infanticide became forbidden in Europe and the Near East during the 1st millennium. Christianity forbade infanticide from its earliest times, which led Constantine the Great and Valentinian I to ban infanticide across the Roman Empire in the 4th century. The practice ceased in Arabia in the 7th century after the founding of Islam, since the Quran prohibits infanticide. Infanticide of male babies had become uncommon in China by the Ming dynasty (1368–1644), though female infanticide remains common today. During the period of Company rule in India, the East India Company attempted to eliminate infanticide but were only partially successful, and female infanticide in some parts of India still continues. Infanticide is now very rare in industrialised countries but may persist elsewhere.

Parental infanticide researchers have found that mothers are far more likely than fathers to be the perpetrators of neonaticide[2] and slightly more likely to commit infanticide in general.[3]