Human birth has a reputation for danger. The usual explanation is simple enough: walking upright narrowed the pelvis, while evolution also favored babies with large ...

Medical intervention in human birth has become so widespread that spontaneous delivery is an increasingly rare event. Yet convincing evidence reveals an underlying 24-hour biorhythm, reflecting a ...

Human birth is far more challenging than that of other primates. In 1960, anthropologist Sherwood Washburn proposed a widely accepted explanation for the tight squeeze a baby experiences passing ...

According to a new study, chimpanzees, like humans, must contend with a confined bony birth canal when giving birth. In humans, the problem was exacerbated by our unique form of upright walking since ...

As billions of people can attest, giving birth is hard for humans. Our infants have an exceptionally large head for their body size and yet have to squeeze through a very narrow pelvis. Appendages can ...

The broader message is unsettling and clarifying at once. Human childbirth is risky, but it may not be uniquely risky. Instead, the research suggests that difficult birth is part of a wider mammalian ...

3D simulation of the birth canal of chimpanzees with (B) the fetal head in a fully extended position, the typical head alignment in apes, and (C) the fetal head in a fully flexed position, the usual ...

Human babies have large heads, and the shape of the human birth canal remains distinctive. The fetus usually has to rotate through the canal in a way that has not been documented in other mammals.