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;
Introduction to Thanatopsis. William Cullen Bryant was a poet who lived and wrote during what is known as the era of Romanticism. Romanticism involved nature, individualism, emotions, and the imagination. Bryant wrote this poem in the early 1800s, most likely in 1813 or shortly thereafter, when there was a great deal of poetry being written about mortality (the poets writing such works were known as Graveyard Poets).