Let me present why I think sexual promiscuity, especially in females is morally objectional from a utilitarian stand point. Utilitarianism, in a nutshell, simply says the most moral action is the one that increases the most happiness for the most people. Pretty much we are asked to find a balance between our pleasure and everyone elses pain. So how do we even determine what our pleasure is worth? Of course, Its impossible to be exact, but approximations can be made. Check out this interesting look at things. http://philosophy.lander.edu/ethics/calculus.html. So in essence there are a couple factors that need to be accounted for...

Intensity (I)--How intense is the pleasure or pain? In the case of sexual promiscuity, especially in females, we can assume a high value for the intensity of pleasure

Duration (D)--How long does the pleasure of pain last? At a time? Probably no longer than 2 hours. In general as long as they are sexually desirable which is actually not a long window in their life time. Think 10 years in 75.

Certainty (C)--What is the probability that the pleasure or pain will occur? Probably pretty high seeing as women can have sex much easier than men

Propinquity (nearness or remoteness) (N)--How far off in the future is the pleasure or pain? Probably within a couple days a female could find a willing sexual partner

Fecundity (F)--What is the probability that the pleasure will lead to other pleasures? Low for women, as we have seen over and over, riding the CC leaves women depleted, jaded, and as we have seen above childless.

Purity (P)--What is the probability that the pain will lead to other pains? These next are where most of the leeway and problems are faced. I personally believe that promiscuity especially in women leads to a lot of emotional pain for them. They have been sold this idea by modern feminism that they need to have all the sex their ancestors did not. Its an idea born from conservative backlash. Its like saying, we already paid for the buffet, might as well take advantage of it. I personally believe women deep down, want to find one or two good men and fuck them a lot. Its interesting when im out in bars and women claim they enjoy sex as much as men, I always ask them, if they could, how many dudes would they bang in a week. The answers range from 2-10, but never more than like 10. If you ask a man how many women he would bang in a week, the answers would be infinity or close to it. Like Patrice O Neal once said "fuck your studies, this is field research nigga"

Extent (E)--How many persons are affected by the pleasure? The whole world. If you arent western society you want to be western society. I personally believe the cost of promiscuity in females is very high to society in general. I believe the climbing divorce rates, increasing acts of random violence, and in general men checking out of society is due to the frustration of their social role as a provider and father being deleted by new age feminism and modern society in general.

In summation, from my point of view (because morality is of course subjective) I think promiscuity in females (a whole different matter than male promiscuity) is morally objectionable because I dont think their admittedly intense, short lived and easily accessible pleasure outweighs the damage that is done to themselves and society in general.