A GF of mine used one as per instructions but still tore 2nd degree. I tore 2nd degree in 3 directions with my first despite only doing little pushes as per midwives instructions - but this time I DID the perineal massage from 34 weeks (well hubby did, I can't bend that way) and had in my birthplan no coached pushing and just slowly eased the head out instead of the light pushing in bursts and only sustained 1st degree grazing (which is already fine and didn't hurt to be stitched either) - so I would recommend doing that instead of the Epi-No, plus if it doesn't work, at least it didn't cost you anything KWIM.
I asked my Ob about the epi-no after it was recommended by a friend. The Ob said not to bother because you go through unecessary pain without the hormones to help you through it, plus they're not guaranteed to work. She said she sees the same percentage of tears from women who use it as those who don't.
However.... my friend swears that the reason she didn't tear was because of the Epi-No.
I'm not using one. Just doing the Pelvic floor exercises and crossing my fingers :P
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