In some babies, the little membrane called the frenulum, which joins the middle of the tongue to the floor of the mouth, is too tight and ‘ties’ the tongue so that the baby has difficulty moving his tongue effectively. This means that the baby will be unable to bring his tongue forward far enough to latch onto the breast and draw the nipple far enough back into his mouth to feed well and he won't be able to form an effective seal around the nipple of either a breast or bottle so he is likely to feed noisily, suck in air as he feeds and tire easily while feeding.
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