<P> In Greece, the missionary position was originally an unpopular position . Beds existed, yet not as we know them today, and men married girls 14 or 15 years of age, which created a height differential . These factors made the rear - entry standing position more convenient . However, circa the second century, Artemidos popularized the missionary position among Greco - Roman Stoics, declaring it "the only proper and natural" position due to the flow of semen . </P> <P> Although the Bible does not mention sexual positions, from the 6th to 16th centuries, some Church authorities taught that intercourse should be face - to - face, man - on - top, primarily because they believed that semen flows with gravity, leading to conception . Exceptions were made for couples dealing with illness, obesity, or pregnancy . According to John Bancroft's Human Sexuality and Its Problems, Thomas Aquinas believed that crimes against nature included intercourse in "unnatural" ways . Protestants did not communicate proper sex positions, and the Catholic Church eventually abandoned its discourse on the topic . Simon Hardy wrote that the missionary position was used to distinguish "bestial and civilized sex ." </P> <P> Others who held that missionary was the only permitted position included Alexander of Hales and the author of De secretis mulierum, who suggested that nonstandard positions might result in birth defects . Ruth Mazo Karras states that William Peraldus' treatise Summa de virtutibus et vitiis distinguished between sins against nature that were "according to the substance" (intercourse other than vaginal) and "according to the manner, as when a woman mounts ." Nicholas Venette's 1770s - era sex manual praised the missionary position as the "common posture...which is most allowable and most voluptuous ." Numerous sources have reported that in the United States, some states had outlawed positions other than missionary between husband and wife, or will grant a divorce to a woman whose husband makes love to her in another position . While many states formerly outlawed oral sex, anal sex, buggery, or other "unnatural" acts, no US law has banned dorso - ventral heterosexual sex, or specified which partner needed to be on top . </P> <P> Among humans, the missionary position is the most commonly used sex position . In his seminal study Sexual Behavior in the Human Female (1953), which focused on American women, researcher Alfred Kinsey stated that 91% of married women surveyed reported using this position most often, whereas 9% reported using it exclusively . A The Journal of Sexual Medicine study entitled What Kind of Erotic Film Clips Should We Use in Female Sex Research? An Exploratory Study selected 18 film clips out of a sample of 90 that were found by the women studied to be particularly mentally appealing and visually arousing. 21% of the original 90 involved the missionary position, but 33% of the final 18 involved missionary . Fewer than 10% of sexually active persons rarely or never use the missionary position . According to Francoeur, the Brazilian Bororo Indians eschew missionary, finding it insulting for either partner to be above the other during sex . Balinese shun the man - on - top position in favor of the Oceanic position due to their perception of the former as being impractical and clumsy . The Cashinahua people use the missionary position to stay stable when they have sex in a forest stream to avoid insect bites . The inhabitants of Inis Beag practice the missionary position exclusively, with very limited foreplay . In addition to humans, the missionary position is also used by certain other species including bonobos, gorillas, and armadillos . </P>

Where did the missionary position get its name