An idiomatic, often derogatory expression meaning someone seems to have been born talkative — very fond of talking or prone to speaking out.
彼はまるで口から生まれたように、初対面の人にもベラベラ話す。
He talks away to strangers as if he were born talking.
あの子は口から生まれるタイプだから、黙っているのは無理だろう。
That kid is the born-talkative type, so staying quiet is probably impossible for them.
謝罪会見でひたすら喋り続けた彼女を見て、ネットでは『口から生まれる』と揶揄する声も出た。
Seeing her talk nonstop at the apology press conference, some online commenters mocked her as 'born to talk.'