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Yes and I'm really too. 3 years ago, had to go back for a 2nd time, but that one was fine. A couple of months ago, I went and got the letter about insufficient cells after a couple of weeks; went back again for the rerun only to receive another letter, but this time saying to wait 3 months. Sooooo annoyed. I always tell them they need the longest speculum they have (sorry if tmi) and it's always pretty "uncomfortable" (ie my fists and jaw are clenched throughout) but it seems they can't reach properly?
Sorry if this is your first time for a repeat: hope it doesn't become a pattern for you as well.
Usually you'd be referred to colposcopy on you third consecutive inadequate test. There's no clear guidance on what the minimum time between tests should be because the reasons for inadequacy differ. It's often suggested a wait of between 1-3 months before having another test. If you have a 'shy' cervix then it might actually be helpful to be seen by a colposcopist as they see a wide range of presentations.