Although hygiene fears alone aren't usually a cause of paruresis, I know from talking to a lot of women that hygiene fears in public toilets can certainly complicate things for some of you.

This article from Starts at 60 looks at those fears and suggests ways of dealing with them.

While some women prefer to hover over a seat rather than sit on it in public toilets, this can make it difficult to relax enough to pee. It can also make you less stable if you're on a train or a plane and there is a sudden movement. You're much more likely to be able to relax safely sitting on the toilet seat, but the advice to wipe the seat and use a disposable toilet seat cover might help to eliminate hygiene concerns. You can easily buy disposable toilet seat covers online in individual packs so that you can carry 1 or 2 with you discretely in a handbag or rucksack.

The only thing I would add is that if you are wiping the toilet seat down before you use it, you would want to be assured of a good supply of hot water and soap to wash your hands afterwards. As this is often lacking in public toilets it's worth also carrying a small travel container of hand sanitiser too.

If you're well-prepared, it's one less thing to worry about.