
Share
12th April 2016
03:16pm BST

It's all based on the theory of 'sex degrees of separation' - but works in data and formulas from the World Health Organisation, the Center for Disease Control and Prevention and other government data from the ONS.
So, if you're a London couple who have both had 10 sexual partners (which this study claimed was the 'ideal' number of sexual partners to have before you settle down) the results are quite sobering.
It means a potential sexual exposure to 1,111,110 partners - that's more than 10% of every man and woman in London.
Worryingly it also means a 19.18% risk of having caught Gonorrhoea and a 16.91% risk of Syphilis.
If you are worried about being at risk from any of these STIs or you just want to be tested for peace of mind, you can look up your nearest NHS clinic services on their website’s location search