The Collaborative International Dictionary of English v.0.48:

Impregn \Im*pregn"\, v. t. [Cf. F. impregner. See Impregnate.]
   To impregnate; to make fruitful. [Obs.]
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         His pernicious words, impregned
         With reason.                             --Milton.
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         Semele doth Bacchus bear
         Impregned of Jove.                       --Dr. H. More.
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