Is it societal? I'd argue it's actually more biological. What's societal is the associated stigma.
Consider the wild state from whence we came: the male of the species produces viable sperm from sexual maturity to, in many cases, death. In an environment where resources are plentiful and so are partners, it is in the interest of his genes' continued proliferation that he impregnate as many females as possible, not least of all because if he doesn't, the other men will.

The female of the species, on the other hand, has a limited span of fertility. There are phases on a monthly basis during which she is completely infertile, and she has a limited number of eggs to offer for the purpose of furthering her own genes. A "successful" sexual encounter also puts her "out of action" for at least nine months, and so it's in her interest to be more restrained and taking greater care in choosing her partners.
(LongJohnBaldry, Mon 17 Jan 2011, 16:03, 2 replies, latest was 15 years ago)

Actually I did read somewhere
that the one bit male biologists like to forget to talk about, is if that scenario is correct then it makes sense for women to have sex with as many men as possible within that period of fertility. It's not actually a case of selecting the best partner at all. I could be wrong but it's an interesting take on it.
( Amberl was stripey and dominated Europe, Mon 17 Jan 2011, 16:10, Reply)

if that were the case
then what would be the point of the fighting and displays etc. designed for the male to show they are the best?
( Vipros. clever got me this far, then tricky got me in, Mon 17 Jan 2011, 16:16, Reply)

That works if the process of gestation and giving birth is as straightforward as going for a haircut.
Unfortunately it's not. We have a nine-month gestation period, which uses up time that could otherwise be spent being fertile. Also, as a species, our offspring spend several years being dependent on their parents for food and shelter. In this case, it is therefore beneficial to the survival of the offspring if the father sticks around to help provide food (as opposed to Mum going out to forage and leaving the children vulnerable). However, this is also an incentive not to get knocked up by a different partner in the meantime - Dad is less likely to stick around to raise the kids if he can't be sure they're his own. This therefore limits Mum's options, so it makes sense to be more choosy about the partner if it might be her only one.
(LongJohnBaldry, Mon 17 Jan 2011, 16:42, Reply)

In this case
Are you refering to mammals in particular as in nature there aare many examples when the male is merely a pair of testicles to be used and the female of the species has the power (that fish thing whose name escapes me at the moment and many spiders etc)? (just being picky about the "wild state" bit)
Again looking at nature and looking at most species other than Humans you see that the majority of females in nature would be termed sluts in human useage as they tend to have sex with multiple partners during their respective seasons, and the males are just there to provide the fluids.
As humans have evolved from a species that has sex just for procreation and turn it into a hobby, I would suggest that the society pressure is the key factor. This I would place at the door of religion meaning that sex is a bad thing and you should only do it for teh creation of life, otherwise like most other mammals when a women was approaching her most fertile (during each monthly cycle) she would be fucking anything with a cock to ensure both successful impregnation and also the greatest chance of genetic diversity.

(I have rambled a bit there and hope it comes across as the coherent argument I have in my head)

edit as teh above has just said while I waffled on and on
(Bonzodog29 is an unemployed sponge of the worst kind, Mon 17 Jan 2011, 16:15, Reply)

I was referring specifically to humans.

(LongJohnBaldry, Mon 17 Jan 2011, 16:49, Reply)

I did realise,
I was merely being an arse,
(Bonzodog29 is an unemployed sponge of the worst kind, Mon 17 Jan 2011, 16:55, Reply)

Well, that's fair enough.

(LongJohnBaldry, Mon 17 Jan 2011, 16:57, Reply)