I had a post coitle test during our long "unexplained" period of infertility. Highly acidic. I did change my diet, but without any luck.

I also read (on a US site) about raw egg white being alkaline and also the right fluidity/ph to help the swimmers along.

The one and only time we braved the use of raw egg white was when we finally concieved successfuly with Olivia.

Not sure if that helps anyone, but it may be worth looking into, if you can stomach it.

Lucy x