Talking about sex is sometimes uncomfortable, unsettling and, for some, un-sexy. Talking about anal sex, though, is a whole other level. Many wouldn't dare bring it up in the first place.

Dr. Evan Goldstein – founder and CEO of Bespoke Surgical, a health practice specializing in gay men’s sexual health and wellness – is trying to change the conversation around anal sex from something strange to something educational and empowering. His book, "Butt Seriously," out this week, aims to do just that.

"Why can't we just meet people where they are sexually?'" he ponders. "No judgment, no stigma, create safe spaces and support so that people get to wherever they want to be."

Yet anal sex is particularly taboo. Experts say that's because many think of it as morally wrong due to lingering effects of homophobia. The only way to combat concerns about the sexual practice is to learn about it.

"Everyone’s got a butt and it’s full of rich nerve endings," which can make anal sex pleasurable, says Dr. Carlton Thomas, a gay GI doctor who posts sexual health tips on social media. "(Anal sex) is for all genders and sexualities. There is no masculinity, femininity, sexuality or gender role assigned to it."

Where does the stigma about anal sex come from?

Anal sex has long been demonized, dating back to religious texts. But cultures including the Romans and Greeks frequently had anal sex anyway, and "it has been represented in art going back thousands of years, including from Asia, South America and Europe," says Debra Lynne Herbenick, professor at the Indiana University School of Public Health and author of "Yes Your Kid: What Parents Need to Know About Today’s Teens and Sex."

The moral stigma has persisted anyway, as anal sex has long been associated with gay men. "Religious discourses that demonize homosexuality and non-reproductive forms of sexual intimacy in particular also shape how the public views anal sex," says Cornel Grey, assistant professor of gender, sexuality and women's studies at Western University in Canada. "When we talk about the stigmatization of anal sex, we also have to confront homophobic stigma as well."

This has even played out in the doctor's office. "Most people don't feel comfortable going to the doctor to talk about these issues," adds Goldstein. "And most doctors don't feel comfortable as well talking about this."

Plus: "There’s this underlying concern about sexual hygiene," says Grey. "If we think about portrayals of anal sex in the media and even within public health literature, there’s very little focus on desire. The focus is often on the dangers of anal sex rather than the pleasure people derive from it." Such dangers include concerns about spreading STIs like HIV, not to mention something as routine as fecal matter.

Though gay men are most often the ones openly talking about anal sex, it doesn't mean they're the only ones having it.

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How common is anal sex?

Statistics vary as to how many people have tried anal sex in their lifetime; it's hard to pinpoint how common it is among both straight and even queer populations. One study from 2017 found that of heterosexual U.S. adults age 25 to 44, 36% of women and 44% of men had tried it. Among queer men, it may not be as popular as society would have us think, though data is limited. One study from 2011 found that of survey respondents who discussed their most recent sexual partner, fewer than 40% had anal sex with them.

It certainly increased in prevalence the last few decades, says Herbenick, and studies over the last 20 years have found that among heterosexual couples, many have tried anal sex but not many have done so regularly.

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When it comes to any kind of sex, remember trust and communication are key

Experts say when it comes to anal sex – like anything else you're unsure of or curious about – do your research. People can and should learn what works best for their body in terms of preparation.

Generally, though, anal sex "is made more comfortable when people use lots of lubricant, are gentle, feel like they can trust one another and are comfortable communicating with one another in case it hurts or they want to go more slowly or stop completely," Herbenick says. As with any other type of sexual act, it's critical to practice safe sex and use protective measures to minimize the risk of STDs.

Because "no, you shouldn't be bleeding with anal sex, and no, you shouldn't have pain," adds Goldstein. If you're in pain, "then clearly something is not right."

Of course, adds Herbenick: "No one should ever nag or pressure another person to engage in anal sex. As with any other kind of sex, anal sex is not for everyone."

And Goldstein doesn't care how someone has sex – "as long as they do it safely, as long as they get the pleasures they want. And if something goes wrong, that they have access to the care that they need."