Before all of you keep on shooting off and saying complete nonsense that has no source in any sefer,here is the exact language of the Matoh Efraim in the 1920 printing that I mentiobned above:
No where is it mentioned that she will have beautiful children or a boy or a girl.
The word segula is never used although I would think that it should be called a segula. Keep in mind again, although the later printing mentions this minhag, earlier printings don’t have it at all. The Munkatcher Rebbe mentions that clearly, that this is a new “minhag” that has no real source in any halacho seforim or minhag seforim. He clearly calls it a minhag shtus. In general, before you say something here, do some research and don’t blabble nonsense.