The Collaborative International Dictionary of English v.0.48:

Fecund \Fec"und\, a. [L. fecundus, from the root of fetus: cf.
   F. f['e]cond. see Fetus.]
   Fruitful in children; prolific. --Graunt.
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

63 Moby Thesaurus words for "fecund":
   abundant, blooming, bountiful, breeding, bursting, bursting out,
   conceptive, conceptual, copious, creative, diffuse, diffusive,
   effusive, esemplastic, extravagant, exuberant, fertile,
   flourishing, formless, fructiferous, fruitful, generous, germinal,
   gushing, gushy, ideational, ideative, imaginative, ingenious,
   inspired, inventive, lush, luxuriant, notional, original,
   originative, overflowing, plenteous, plentiful, pleonastic,
   pregnant, prodigal, productive, profuse, profusive, proliferous,
   prolific, propagating, redundant, reiterative, repetitive,
   reproducing, rich, seminal, shaping, spawning, superabundant,
   swarming, tautologous, teeming, thriving, uberous, visioned