Hi Nic, thank you for replying.
Glad I am not the only one who has seen the white stuff, I have now seen it twice on my lawn, where the hedgehogs have been going round and round in circles, huffing, puffing and nudging one another.
I can tell you though, I did ask the same question on a Hedgehog face book page I belong to (after asking on here) and many others have found the same stuff, one lady even shared a photo of what she had found. They seem to find it after Hedgehogs have been trying to mate.
One gentleman who rescues Hedgehogs did reply that it is sperm and a few other people said the same, so I do feel it is sperm.
Never seen it before in my garden until the female turned up, interesting what you find out and see.
The female still (from what I have seen so far on video footage) hasn’t surrendered and they have so far spent up to seven hours going round and round in circles, she has been letting him rub his face round hers, so fingers firmly crossed.