Hmm - the verb is chiefly US usage, according to OED.
[Early ME. byr{th}(e, bur{edh}(e, bir{th}(e, probably, since the form is foreign to OE., a. ON. byr{edh}(i)r str. fem. (OSw. byr{th}, Da. byrd), genit. bur{edh}ar (on which Icelandic formed a new nominative bur{edh}r masc.); = Goth. ga-baur{th}s:{em}OTeut. (ga-)bur{th}i-z, f. the stem of ber-an to BEAR, with suffix -{th}i- (= Aryan -ti-s, cf. Skr. bhrtÃs, OIr. brith). The OTeut. word had shifting stress, and consequently, according to Verner's law, {th} and d interchanged in the inflexion: in ON. and Goth. these were levelled under {th}, but in WGer. under d (High G. t), in OS. giburd, OHG. giburt, burt (MHG., mod.G. geburt), OE. {asg}ebyrd. The latter was prob. the source of ME. BIRDE, burde, ?race, descent?; but could hardly be that of birth, unless the latter was assimilated to ns. in -{th}, -{th}e, or influenced by ON. For the final -e of ME. byr{th}e, cf. ME. der{th}e a. ON. dyr{edh}, and see -TH1.] Tee hee!