A recent study published in the Journal of Infectious Diseases found that the most important factor in increasing the risk of an HIV-infected person passing on the disease to his or her uninfected partner is the level of HIV in the blood. Additionally, researchers confirmed that using protection can significantly reduce the risk of passing on the disease.

By analyzing a group of 3,297 couples in sub-Saharan Africa in which one person had HIV and the other did not, the researchers were able to determine the risks of the uninfected individual coming into contact with the disease. The participants had to enroll in a randomized trial of acyclovir suppressive therapy and then had to have frequent follow-ups. The study's authors estimated that the rate of the risk of HIV transmission per number of times one has sex is about 1 every 900 acts. However, condoms can decrease this risk by as much as 78 percent.

"Our results underscore the importance of antiretroviral therapy, and, possibly, treatment of co-infections, to reduce plasma HIV-1 viral load in HIV-1 infected partners, and condom promotion, male circumcision, and treatment of symptomatic sexually-transmitted infections for HIV-1 uninfected partners as potential interventions to reduce HIV-1 transmission," the authors wrote.

According to the Centers for Disease Control and Prevention (CDC), people between the ages of 13 and 64 should have an HIV test at least once during their lifetime in order to determine if they are infected. Those who are at a high risk of developing the disease should be tested on a yearly basis. Use latex or polyisoprene condoms to prevent the transmission of the disease because other condoms made of "natural" products such as lambskin are not as effective.

1. Personal vibrators

One of the best ways to kick things up a notch in the sack is to introduce toys into your routine. Vibrating devices not only add stimulation to what is already a wild experience, but also allow partners to keep things spicy and fresh.

Guys may be afraid that their girlfriend or wife will only want to use a vibrating device when he's not around, but that is far from true. Many products, such as the LifeStyles® a:muse™ Personal Pleasure Massager, are designed for couples to use together.

And ladies, don't think that your man won't be happy with a little vibrating present himself. For instance, the LifeStyles® Vibrating Ring™  is ideal for the horny man in your life. Once your guy unwraps this present and tries it on for size, he'll be thanking you for your thoughtfulness in more ways than one.

2. Underwear

Who doesn't love a new pair of undies? This Valentine's Day, get your partner something that will make your foreplay all the more exciting. Though not everyone will be able to appreciate your lover's new skivvies, once the clothes come off and the lights are turned down low, a new pair of briefs for him and a sexy new bra for her will help set the mood.

If you're new to the relationship, you may not know what type of underwear your partner prefers. Fear not – this gives you the perfect excuse to go shopping on February 14. Have your babe take you to their favorite store – and don't be afraid to ask them to model some of the undies in the dressing room. Once they find a pair they (and you) adore, be sure to pull out your wallet or purse before they're given the chance to pay for it on their own.

3. Condoms

We know what you're thinking – condoms? For Valentine's Day? But never underestimate the sensuality and tenderness of safe sex. Buying condoms for your loved one will let them know that you want to get down and dirty while still staying clean.

Girls, why not purchase flavored condoms? This gift might make him giggle initially, but it's sure to come in handy during some intimate moments.

Guys, condoms can be a great gift for the woman in your life as well. If buying for a lady, show her you care by picking out a rubber designed specifically for her pleasure, such as ®LifeStyles 3Sum Condoms.

4. Something Kinky

This is a suggestion for the couples who may want to let their darker side out in the bedroom. There are a number of potential gifts – from mild to wild – that can be classified as "kinky." Of course, it's important to make sure you and your partner are on the same page before picking up a pair of fuzzy handcuffs. But if both of you are eager to try something new, then make this Valentine's Day about whatever tickles your fancy.

The syndrome was the subject of a recent study conducted by specialists at the University of Turin. The results were published in the British Journal of Urology International this month.

"Penile size is a matter of great interest among men who are affected by 'short penis syndrome' or just believe themselves to have a small penis, even though the dimensions of the organ fall within the normal range," said Marco Oderda, a urologist who contributed to the study, according to the news source.

The condition likely stems from the amount of advertising concerning penis size that men are subjected to on a daily basis. These include commercials for male enhancement, and general depictions of "typically masculine" men in the media.

"We equate masculinity and power with penis size," Ira Sharlip, clinical professor of urology at the University of California at San Francisco, told WebMD. "Of course, there's really no relationship."

The New York Daily News lists some tips for men who suffer from short penis syndrome.

First, if you have a few extra pounds around the gut, it may be time to take up an exercise and diet regimen. An overhanging stomach can cause a penis to look smaller than it actually is.

Additionally, trimming pubic hair can help, as a thicker bush "down there" can obscure an inch or two.

Lastly, it may be wise to visit a sex health expert to discuss the issue and ask any other questions you may have about sexual health information.  

The respondents, all of whom were between the ages of 18 and 49, answered questions about fidelity, sexual positions, condom use, fantasies and the number of sexual partners they have been with, among other topics. The input from respondents will help the condom manufacturer enhance the sexual experiences of their customers.

"At LifeStyles, we are constantly searching for ways to make safe sex better," said vice president of Marketing for Lifestyles Carol Carrozza. "By listening to feedback and discovering the habits and desires of sexually active individuals, we are able to tailor product releases and innovations according to their needs and wants, giving our users the most advanced products possible to enhance their sex lives."

The surveys will continue each week, and anyone who falls within the age range is invited to participate by visiting the LifeStyles website. Topics that will be highlighted on the site as well as on the company's social media pages on Twitter and Facebook include "Her Top Fantasies," "His Favorite Positions" and "What She's Open to Trying."

There have already been a number of interesting factoids unveiled by these surveys. For instance, around 41 percent of males who took part in one survey found that the fit of the condom is essential, as a contraceptive that is too tight or too loose decreases sexual satisfaction. Not only that, but an ill-fitting condom can also be a roadblock for STD prevention.

There has been plenty of positive sexual news uncovered by the LifeStyles surveys. A whopping 90 percent of respondents said they were "satisfied with their sex lives."

While there has been extensive research on surgical procedures to lengthen one's member (which often carries complications), there has been little analysis of so-called penis pumps and other non-invasive methods of enlarging the penis. The researchers from UT created a review of some devices that proved popular, and found that they had succeeded in extending penis length at least slightly.

Researchers Marco Oderda and Paolo Gontero reviewed several studies on devices such as vacuums, penoscrotal rings and even penile exercises. One study outlined in their report found that a stretching device increased some men's penis length by 1.8 centimeters. Another device was able to elongate a flaccid penis for three months.

Additionally, the penile extending devices outlined in the reports carry a low risk of complications and most patients find them to be generally tolerable.

Demand for such devices may be on the rise due to the fact that more and more men have misperceptions about the average or "normal" penile length. This may be due in part to pornography, which typically features men with bigger-than-average tools.

"The idea that the penis is the most important part of your body underlies so many of men's sexual problems," Cory Silverberg, a safer sex education professional, told WebMD. "One of the biggest sex myths for men is the notion that we are our penises, and that's all that counts in terms of sex."

Being comfortable with the size of your penis may play a part in safe sex. When it comes time to buy condoms, knowing the length and girth of your penis will help choose the right size contraceptive. 

Those who visited a sex clinic in San Fran 100 years would be referred to as "unfortunates," who suffered from "social maladies." The diseases themselves were given the blanket term, "venereal disease," a phrase that has mostly fallen out of favor in recent years.

"We try to have a much more positive attitude," Dr. Susan Philip, director of STD Prevention and Control at San Francisco's Department of Public Health, told the news source. However, she added that some practices, such as providing treatment for STDs free of charge and maintaining client confidentiality, were put in place during the early years of sexual health initiatives.

Advocates of safer sex education gathered on Monday, May 2, to hear speakers discuss the history of STD prevention in the city at an event titled 100 Years of Sex. Phillips spoke, along with Steven Tierney, president of the San Francisco Health Commission, according to the news source.

Other speakers discussed how times have changed. Dr. Gail Bolan, who began working in the field of STD prevention in the late 80s, talked about how syphilis had gone from a nonexistent issue to a serious health concern since her career began.

Phillips also spent some time remarking on the future, stating that "we're not done yet. We have miles to go," according to the news source.

There are still many people who don't know that wearing a condom is one of the best ways to protect themselves and their partners from sexually transmitted diseases, according to the Centers for Disease Control and Prevention.

Researchers used the term "partner betweenness" to describe situations in which a woman is closer with a man's friends than he is himself. This may cause the man to feel as though his partner is a wedge between him and his social network, causing a rift in the relationship.

"Men who experience partner betweenness in their joint relationships are more likely to have trouble getting or maintaining an erection and are also more likely to experience difficulty achieving orgasm during sex," wrote professor Benjamin Cornwell, one of the study authors.

The heart of the issue of partner betweenness lies in masculinity. According to the researchers, "autonomy and privacy" are essential for men to feel secure in their masculinity, and the perception of a partner moving in on his social network may make him feel emasculated.

There are a number of ways men who are struggling with erectile dysfunction can overcome the issue. According to WebMD, talking about sex and any issues one has in the bedroom can help, so counseling is definitely a viable option. Couples can also look into using a pleasure condom to enhance the bedroom experience.

While it may not be a good idea for a woman to be closer to a man's friends than he is, the researchers pointed out that shared social networks are still beneficial for couples.

"We always encourage youth to have conversations with their parents, but we also recognize that not everyone has that ability," Alison Macklin, director of community education for a Colorado Planned Parenthood branch, told the news source. "We're not trying to take the place of those conversations, or providing firsthand knowledge, but rather we're providing a way to help answer questions."

ICYC was originally part of the Denver Teen Pregnancy Prevention Partnership, which was launched in public schools in Denver in 2007. In 2010, Planned Parenthood took over the program, and since then, teens have submitted around 500 messages. The organization hopes to double that figure in the coming year.

Teens can ask questions up to 160 characters, the typical length of one text message, and expect a response to their query within 24 hours. Macklin says the program will help teens get essential information about sex from reliable sources in a format they understand.

Teen sex education is important to maintain the health of young, sexually active individuals. Planned Parenthood has been promoting community healthcare for over 90 years.

To understand the study, one must have an understanding of basic evolutionary theory, namely survival of the fittest. Physical traits often determine what will be attractive to potential partners, and typically, in monogamous heterosexual relationships, more masculine traits are more stimulating to women, particularly when they are ovulating.

This has been proven in previous studies, according to the researchers, to indicate that women prefer bigger, hairier men. This trend is also prevalent in the animal kingdom. Male members of certain species often have large, dramatic characteristics, such as the tail feathers of the peacock, in order to prove their masculinity and draw more mates.

To test the theory between voice depth, a typically masculine trait, and semen quality, researchers had a group of young men record their voice. Afterward, they each gave a sample of their semen. Their voices were then played for a group of women who rated the male voices depending on how attractive they found them. Scientists also conducted sperm counts on the samples collected.

As expected, the women on average described the deeper male voices as more attractive. However, there appeared to be no correlation between "men's sperm motility parameters and voice pitch, rated voice attractiveness, or rated voice masculinity," the researchers wrote.

No matter how deep your voice is, sperm quality doesn't always determine whether or not you will get your partner pregnant. It's always best to err on the side of safety and wear condoms, not only to prevent unwanted pregnancy, but also as a form of STD prevention.

This method works very well for some people, but for others it can be disastrous. Below, we'll discuss some of the most common questions those considering such an arrangement may have.

Is it right for me?

The first step before trying out a regular bedroom pal is to decide if it's right for you. First and foremost, if you're the type of person who tends to get jealous quickly, you should probably consider an alternate route. It's possible that the partner you choose will have other "special friends" as well, and if that thought irritates you, then you may want to look for boyfriend or girlfriend material instead. This is also the reason that practicing safe sex is important – you need to protect yourself from any sexually transmitted infections your buddy may pick up elsewhere.

Additionally, if you know you quickly form emotional attachments after sex, then you may be putting yourself on the road to disaster by choosing to have a friend with privileges. Remember, part of the definition of the practice is avoiding romantic feelings, and if that's to be inevitable, then stick to the one-time encounters until you find something more permanent.

Where can I find my buddy?

Once you've decided to go for it, the next step is finding the right person. Though the term includes the word "friends," it's not always wise to tap your own social group for this endeavor. Remember, if things don't go well, it may be difficult to keep in contact with this person, so you don't want to jeopardize a friendship that is close to your heart.

Instead, consider acquaintances with whom you have some social distance, but who are attractive to you. If you can't think of anyone in your daily life, it may be time to turn to previous hookups. Have you had a one night stand that was particularly enjoyable? Perhaps you went on a date with someone who didn't share much chemistry, but was a firecracker in the sack. Whip out the cell phone and check your list of previous sexual conquests – one of them may be perfect for the regular booty call.

How can I make sure this doesn't end in disaster?

Even for the most emotionally detached, sexually open person, feelings may develop or things may turn sour. One way to make sure the casual relationship doesn't blow up in your face is regularly talking about sex, emotions and desires with your counterpart. If you feel romantic emotions beginning to form, or you sense them in your partner, confront it head on. Don't be offended if they find another partner and want to become monogamous with him or her – after all, friends with benefits are temporary arrangements in most cases. Lay out the parameters of the relationship from the start, and discuss any alterations you may need to make – including calling it quits.