'fertility-promoting' is a compound of 'fertility' and 'promoting.' 'fertility' originates from Latin, specifically the word 'fertilis' (via Old French 'fertilité'), where 'fertilis' meant 'fruitful' or 'able to bear offspring.' 'promoting' comes from the verb 'promote,' which originates from Latin 'promovere,' where the prefix 'pro-' meant 'forward' and 'movere' meant 'to move.'

'fertility' passed into English via Old French 'fertilité' and Middle English forms before becoming the modern English 'fertility.' 'promovere' changed through Old French ('promouvoir') into Middle English ('promoten'/'promote'), and the present-participle adjective 'promoting' derives from that verb form.

Initially, 'fertilis' referred to being fruitful or productive in a literal, agricultural or biological sense; this basic sense remains in 'fertility.' 'Promovere' originally meant 'to move forward,' and its sense broadened to include 'to advance or encourage,' which is the sense carried in 'promoting.' Together, the compound now means 'encouraging or causing fertility.'