10 Surprising Things You Might Not Know About Sex

Remember those pamphlets you got during awkward Sex Ed classes back in junior high that said, "Am I Normal?" and featured a frizzy-haired 13-year-old girl wearing a worried look? Inside the pamphlet were various facts and statistics about puberty and sex that did as much to ease your nerves as a trip to the mall with mom to shop for a new bra. Well, you may be older and wiser now and more comfortable in your skin, but if you're like me, you're still a little bit curious what constitutes "normal" between the sheets and under one's clothes. After the jump, a list from LifeScience.com of ten surprising -- and, not so surprising -- sex statistics. 

10. "An 18th-century Russian woman holds the world record for having birthed the most children: 69, which she had over the course of 27 pregnancies that included sixteen pairs of twins, seven sets of triplets, and four sets of quadruplets. But she's outdone by the male record-holder for most kids, a Moroccan emperor who, according to the Guinness Book of World Records, sired ‘at least 342 daughters and 525 sons, and by 1721, he was reputed to have 700 male descendants.'"

9. "The average erect penis is five to seven inches long, and four to six inches in circumference."

8. "Approximately 5 percent of 40-year-old men and between 15 to 25 percent of 65-year-old men experience erectile dysfunction." Hmm, I guess we're sort of lying when we tell guys, "It happens to everyone!"

7. "The average male loses his virginity at age 16.9; females average slightly older, at 17.4. And a new study shows that genetics may be a factor: inherited traits, such as impulsivity, can make a person more or less willing to have sex at an earlier age."

6. "About one out of 10 married adults say that they typically sleep alone." No word on where do their spouses sleep…

5. "While 75 percent of men always reach orgasm during sex, only 29 percent of women report the same. In addition, most women are unable to climax through vaginal intercourse, instead needing clitoral stimulation."

4. "Two-thirds of college students have been in a 'friends with benefits' relationship, citing the lack of commitment required as the main advantage to such an arrangement. More than half of those who had sex with a friend said they had engaged in all forms of sex; 22.7 percent said they had intercourse only, while 8 percent said they did everything but have intercourse."

3. "According to a survey of adults aged 20 to 59, women have an average of four sex partners during their lifetime; men have an average of seven." Well, we already knew that, didn't we?

2. "Two-thirds of women who had their first baby between 2001 and 2003 worked during their pregnancy, and 80 percent of those women worked within one month or less of giving birth. Compare this to the period between 1961 and 1965, when 44 percent of women worked during their pregnancy (35 percent worked one month or less before delivering)."

1. "At least 50 percent of sexually active men and women will have a genital HPV infection at some point in their lives. HPV, or human papillomavirus, comes in both low- and high-risk forms; low-risk HPV can cause genital warts, and high-risk can cause cervical and other cancers. In 90 percent of cases, the body's immune system will fight off the disease within two years."