My now 19 month old daughter was potty trained at 18 months and was going on the potty on her own with no accidents for 3 weeks straight. She would run to the potty when she needed to go without even being reminded which is how i know she knew to go on the potty to pee. then all of a sudden one day she decides she is no longer going to go on the potty. a complete 360. What should i do? I did the potty training technique of running around naked and it worked, should i go back to that?
This is called a 'potty pause' and is extremely common.
First of all, you need to rule out physical causes. Is she constipated? Could she have cystitis or a urinary tract infection? If it hurts her to poo or pee she will resist doing so until she can't keep it in any longer. (Constipation can cause pee accidents as well, as the backed-up poo in the rectum will press on the full bladder. If she has a blockage further up, then some liquid poo might get round it and come out on its own.)
Secondly, has she had a bad experience that has put her off? Perhaps some well-meaning person has been trying to force her on the potty when she didn't want to, or failing to provide a potty when she needed one. Or maybe there's been a big disruptive event (like moving house, a holiday, or a relative arriving/moving out)? These can cause regression in all sorts of areas as the child diverts processing power to dealing with the changes. Once a bit of time has passed and the experience has faded, she should go back to her previous behaviour. In the meantime, try and tempt her back on with a new potty, or a toilet seat adaptor, so the novelty will be exciting.
Or it could just be that life is too exciting to break off and go to the potty. Go back to potty training – bare bum when you can so she has the feedback of wetting herself, tell her she's peeing when you see her doing it (but don't tell her off – this is known to be counterproductive), and have a potty in every room she uses regularly so that the sight of it will be a reminder and she won't have to go too far. Tempt her to stay on with 'potty toys', things she doesn't have at any other time, or a book. Books about using the potty, or poo in general, are particularly good. My daughter is particularly fond of simple jigsaw puzzles.
Did she have any sort of signal she used to show that she needed the potty if she couldn't get to one? If not, try and introduce one – a sign or gesture that you always use when you say 'potty' or when she's on one. She might well pick it up and sign it back to you when she needs to go, even if she doesn't make a move towards the potty. Also, look out for non-conscious signals and point them out to her. 'You're standing with your knees bent and jiggling about. That might mean you need to pee. Let's have a try on the potty.'
If she already knows how it feels when she needs to go and what to do about it, this stage won't last long. She'll soon get tired of having to interrupt what she's doing to get her wet clothes changed. Just keep talking to her and looking out for signals to help her communicate.