There are many advantages to giving birth in positons such as squatting, kneeling or getting on your hands and knees, rather than lying on your back. X-rays have shown that the pelvic outlet becomes wider when squatting or on your hands and knees, which helps to shorten labor.
The evidence largely suggests that lying on your back during birth prolongs labor, and slows contractions, yet the majority of women in the US give birth in this position.
So how did humans end up giving birth in this position in the first place? Well, the answer is basically because a perverted king enjoyed his wives giving birth in this position way back in 17th-century France. The position has only been widespread in Western culture for the past 200 years, and King Louis XIV is to blame.
"Prior to this time, the recorded history of birthing indicates upright birth postures were used extensively," Professor Lauren Dundes writes in the American Journal of Public Health.
King Louis XIV had 22 children over his lifespan (1638 -1715). As a king, he had very good reasons to have many children, given that he needed a guaranteed heir to the throne. But he also apparently liked to watch his wives and mistresses pushing out his children.
Louis "enjoyed watching women giving birth, he became frustrated by the obscured view of birth when it occurred on a birthing stool," Dundes writes. Because of this he "promoted the new reclining position. He also insisted on male accoucheurs [midwives] attending births."
Scholars have claimed that he liked to watch for "perverted" reasons, according to the study. The masses may have been influenced by the King, who actively promoted the birthing position, and it has since spread from there.
"The influence of the King's policy is unknown, although the behavior of royalty must have affected the populace to some degree. Louis XIV's purported demand for change did coincide with the changing of the position and may well have been a contributing influence."
Since that time the position has dominated, despite its disadvantages. It's still used today in Western cultures, all because hundreds of years ago a creepy voyeuristic king liked to watch.