(THE TIMES) 10 September 2006:

It’s long been noted that sex makes people happier and more contented, but researchers at State University of New York have found something that might surprise some: the method of contraception used has a greater effect than previously thought.

Men have complained ever since their invention that condoms reduce sensitivity and thus the pleasure derived from the act but it appears that they reduce female pleasure as well. The hypothesis is that there are hormones in semen that are absorbed by the female membranes, said hormones contributing to female happiness.