Perhaps psychologically, sympathy pains allow the man to go through the pain with the woman, so she doesn't have to do it alone. According to one article I unearthed on the subject, though, there is a biological foundation for these feelings. Men with pregnant partners were shown to have an increased level of estrogen and a decreased level of testosterone in one test.
William Blake (1757-1827) , English artist, mystic and poet wrote Songs of Innocence (1789): a poetry collection written from the child s point of view, of innocent wonderment and spontaneity in natural settings which includes Little Boy Lost, Little Boy Found and The Lamb;
... bodies forth The forms of things unknown, the poet's pen Turns them to shapes and gives to airy nothing A local habitation and a name. William Shakespeare derived his ideas both from his own imagination and from a wide range of earlier sources.The main source of ideas for many of William Shakespeare's plays on classical themes was Thomas North's 1579 English translation of Plutarch's Lives... bodies forth The forms of things unknown, the poet's pen Turns them to shapes and gives to airy nothing A local habitation and a name. William Shakespeare derived his ideas both from his own imagination and from a wide range of earlier sources.