Here is an article from WebMD explaining the long list of other reasons women might sign up for that monthly packet of bubble-wrapped pills, even if they don't actually have a sex life at the time:
Other Reasons to Take the Pill
I personally have used the pill for at least two of those reasons. Google "other reasons to take birth control" and you'll see a whole list of similar citations from all sorts of sources; WebMB, as far as I know, is a purely medical site. I also know from experience that, even if you really don't want to get pregnant, the symptomatic relief of menstrual symptoms that the pill gives can be nearly as important to your personal life. For a very balanced discussion of the issues, read Beyond Birth Control, from the Guttmacher Institute.
It's impossible to discuss this topic from either side without sounding sexist. The human race comes in two genders, with totally different plumbing and hormonal environments; and in my experience, neither side understands the other's situation very well. Some men in particular don't even seem to want to understand the implications of living in a body that bleeds for a week every month (associated with pain that sometimes stops you in your tracks) - it's yucky and they'd rather not think about it. Sorry, guys, I'm going to horrify you and talk about it. For a single woman who doesn't get paid unless she goes to work, the ability to control serious menstrual distress so she won't miss a day can be critical. Believe me, many employers will fire you if you miss one day of work a month.
Wikipedia's article on the menstrual taboo cites a 1981 study which found (emphasis mine):
A substantial majority of U.S. adults and adolescents believe that it is socially unacceptable to discuss menstruation, especially in mixed company. Many believe that it is unacceptable to discuss menstruation even within the family.This attitude is still around thirty years later, and may explain something that has puzzled me: except for the Catholic bishops, most of the men who have been ranting about the evils of contraception are married. They have wives, and I guarantee you, those wives either menstruate now or have previously done so. Do their husbands actually not understand about this? Have they never discussed it? Given the attitudes revealed in that study, maybe they don't. Which raises the issue, maybe they should.
The most annoying feature of this debate is that the who-pays-for-health-care issue is being drowned in the screaming over whether women should be able to decide not to have babies for awhile. The real issue isn't contraception - it's contraception that is paid for by health insurance. And in this Presidential campaign year, it's contraception that must be paid for under the new health care law.
The argument comes down to this: are we willing to provide hormone therapy treatment for all women, or only for women rich enough to front it themselves? Which would include the wives of the men who rant about paying for contraception for poor women because it infringes their religious freedom.
We have the most rationed health care in the world: health care rationed by luck. Are you lucky enough to work for an employer with a paid plan? You're in. Are you self-employed and not very well off? Do you work for a firm too small to pay for a plan? You're out. And if you're out and need serious health care, you either won't get it (and may die), or you will get it and they'll bill you directly, at a rate several times higher than they charge the insurance plans they deal with (which will bankrupt you).
Are we willing to pay for the health care that everyone needs, when they need it (and at the same rate for everyone), or shall we continue as we are? That is the question, ladies and gentlemen. That is the question.