From Rudy Giuliani’s prostate to Tom Green’s testicle, men’s private parts have been on public parade of late. In the opening pages of his new book, "Sexual Health for Men: The Complete Guide," Harvard endocrinologist Richard Spark ties the new willingness of men to publicly discuss the fallibility of their love tackle directly to the 42nd American president and a little blue pill.

Using the randy commander in chief and Viagra as a jumping-off point, Spark delivers an encyclopedic guide to all things male, from discolored semen to the viability of alternative erectile treatments. "Sexual Health for Men" is instructive, calming and frequently entertaining.

During a recent interview, Spark discussed his version of the Clinton legacy, shifting attitudes about male sexual health and alternatives to Viagra. Oh, and then there’s the one about Dr. Brindley and his performing penis ...

The first paragraph of your book mentions President Clinton. The second paragraph mentions Viagra. Can you talk a little bit about the pivotal part the president and Viagra played in opening up the discussion of male sexuality?

We really didn’t talk much about male sexuality in polite company until the episode with Clinton and Monica [Lewinsky]. That sort of opened the floodgates. Fortuitously, almost two months to the day when the article regarding Clinton and Monica appeared in the papers, the New York Times had their first Column 1 story about the fact that Viagra was being approved. Everybody was chatting about Viagra, from Maureen Dowd to Jay Leno. After that, the whole issue of men’s sexuality became open game.

You write that Viagra legitimized male sexuality not only as conversation material but as a valid health-care issue.

Absolutely, because men who had problems with sexual health didn’t discuss it. But now, when doctors [ask about sexual function], they’re being surprised to hear men say, "I’m glad you brought it up, doctor, because now that you mention it ..."

Are there specific at-risk populations in the field of men’s sexual health?

The major at-risk group are the smokers. [Then there are] the people who have certain other problems like diabetes mellitus, certain individuals who abuse recreational drugs -- cocaine, for example, is a stimulant initially, but eventually has a negative effect on a man’s sexual function. There are other men who take medications designed to treat problems like high blood pressure or depression who can experience side effects that interrupt their sexual function. All of this is gone over in the book; we try to cover every area.

Even down to the effects of bike riding.

Well, bike riding is one thing that has been a source of great interest to the cyclists of America. There have been some studies reported on cycling and its impact on a male’s potency, and we review those in some detail in the book. The difference is that the studies have been done on the real champion bike racers. The people who are cyclists in my practice tell me that the average cyclist who is out for the weekend jaunt or something of that nature does not place himself at the same degree of risk as the individual who is doing these marathon bike races, where he is constantly putting pressure on his genital area and perineum and compressing the nerves that are important to use to allow erections to occur.

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