I don't have a dissertation on the topic, but have read Andy Rooney's My War several times, he mentions the sex that was freely available to the GI's who liberated Paris in August of '44. There's a specific quote he credits WW2 correspondent Ernie Pyle with: "Any GI who doesn't get laid tonight is a sissy".

I can't imagine that they'd have any -less- luck getting laid Stateside or in London, wherever else. Young men in uniform being on the winning side with a pocket of money present an attractive package, especially when the entire world is reacting to the cessation of the largest, most violent conflict of all time. Here is an article referencing a letter written by a British officer's wife on VE Day, it mentions the crazy celebrations and couples having sex in the dark outside of Buckingham Palace, among other things.

So while I can't point you towards a multi-volume treatment of the subject, cursory examination of primary sources indicates that yes; American and British soldiers probably had no difficulty whatsoever in finding women for consensual, celebratory sex in the days/weeks/months after the war.

For a lot of them though, VE and VJ Day didn't mark the end of the war. After VE Day there was still the war with Japan to think about, to say nothing of the giant snaffle that all of Europe was tangled up in after all that conflict. Occupation duty, sorting out the winners and losers, dealing with refugees, provisional governments, militias, war criminals, and attempting to restore law, order, and social services would prove to be a task that was arguably harder than winning the damn war in the first place.

According to Simonoff's "Smoothing Methods in Statistics" there was a sharp increase in the birth rate in the US starting in January 1946 (Early February was 40 weeks after VE Day, May 8, 1945)

This doesn't indicate the frequency of non-successful coitus, but it is definitely an indicator of increased sexual activity.