Quote
"Man alone at the very moment of his birth, cast naked upon the naked earth, does she abandon to cries and lamentations."
"The present exploratory study measured pain and tactile thresholds in response to mechanical stimu-lation of the hand before labor, during labor, and after parturition in women. In women who had Lamaze childbirth preparation (but not in women who did not have childbirth preparation), pain thresholds were significantly higher during labor (determined up to 8 cm cervical dilatation) than prior to labor and 24 hours postpartum. Tactile thresholds did not change during any of these conditions. These findings support earlier findings in this laboratory that vaginocervical mech-anostimulation elevated pain thresholds in human and animal subjects, and more recent findings that pain thresholds increased in rats during delivery of individual young. The present findings suggest that an endogenous process that attenuates the pain of parturition is activated when the cervix dilates during labor."

Birth is the act or process of bearing or bringing forth offspring, also referred to in technical contexts as parturition. In mammals, the process is initiated by hormones which cause the muscular walls of the uterus to contract, expelling the fetus at a developmental stage when it is ready to feed and breathe.
"Man alone at the very moment of his birth, cast naked upon the naked earth, does she abandon to cries and lamentations."
"The dew of thy birth is of the womb of the morning."
"When I was born I drew in the common air, and fell upon the earth, which is of like nature, and the first voice which I uttered was crying, as all others do."
"BIRTH, n. The first and direst of all disasters. As to the nature of it there appears to be no uniformity. Castor and Pollux were born from the egg. Pallas came out of a skull. Galatea was once a block of stone. Peresilis, who wrote in the tenth century, avers that he grew up out of the ground where a priest had spilled holy water. It is known that Arimaxus was derived from a hole in the earth, made by a stroke of lightning. Leucomedon was the son of a cavern in Mount Aetna, and I have myself seen a man come out of a wine cellar."
"A man is born alone and dies alone."
"As some divinely gifted man, Whose life in low estate began, And on a simple village green; Who breaks his births invidious bar."