The act of having your male friend or brother get your wife or girlfriend pregnant.
Man 1: I've been trying to get my wife pregnant, but the doctor says I have a low sperm count.

Man 2: Your wife is hot! You should let me have sex with her to get her pregnant... You know, IN VIT-BRO FERTILIZATION.
by TwoFacedJG135 January 23, 2012
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