Sylvia Plath (1932-1963)
All the metaphors relate to herself or to her pregnancy, except those in lines 4-5, which refer to the unborn baby: growing round and full like an apple or plum, seeming precious as ivory (and with ivory skin), fine-timbered in sinew and bone like a well-built horse.
The tone of the poem is clear, if complicated. Humour and self-mockery are evident in the image of the elephant and strolling melon. In the last line, there’s a note of wonder at the certainty of gestation and birth: “Boarded the train there’s no getting off.”
On a higher level of abstraction, gestation itself can be seen as metaphor for another product – poems and other creative works.
Sharma, Kedar N. "Metaphors by Sylvia Plath: Introduction" BachelorandMaster, 28 Apr. 2014, bachelorandmaster.com/britishandamericanpoetry/metaphors-introduction.html.