Just when you think you know something about women, turns out there's more than meets the eye. At least from a scientific point of view. For example, did you know that female ejaculate is similar to male ejaculate, minus the sperm? Yeah, we didn't think so. Here are five fun facts you may not know about women. Now you can impress your friends with your extensive knowledge of the female body. That is if you can do it without looking like Brainy Smurf. No.5: Women taking birth control can be perceived as less attractive As most of us know, the pill prevents pregnancy by inhibiting ovulation. Nothing earth shattering there. But Dr. Alexandra Alvergne and her colleague Dr. Virpi Lummaa of the University of Sheffield found that the unfortunate side effect is a reduction in woman’s attractiveness. Over the course of a normal menstrual cycle, hormones fluctuate, vocal pitches change and even body odors are altered. During ovulation, these subtle changes increase a woman’s attractiveness because they signify fertility. It’s hard to believe that men could even pick up on something simple as ovulation. Yet they do. A 2007 University of New Mexico study found that strippers actually earn more money when ovulating. A significantly higher $70 an hour vs. the average $35 for a woman menstruating, and $50 when a woman is neither menstruating nor ovulating. No.4: Birth control can interfere with a woman's ability to assess a mate It’s hard enough trying to pick a long-term partner; throw birth control in the mix and a woman’s ability to meet Mr. Right can become completely twisted. Under normal circumstances, a woman subconsciously chooses a man who would make a good genetic match. But if she’s on birth control, the hormonal deluge flips her senses. For biological purposes, women prefer a mate who is genetically different from them to decrease the chance of abnormalities in offspring. But according to a 2007 University of Liverpool study, birth control throws a wrench in nature’s grand plan by causing women to choose men who are genetically similar to them. Though no one is 100% sure why the pill affects attraction, some scientists theorize it may affect marriages in the long run. A woman on the pill might start dating a man similar to her genetically only to find she is no longer attracted to him once off the pill. Food for thought if you’re dating someone on the pill. No.3: Orgasms can relieve menstrual cramps Tell your lady to put away the Midol and just do you. A healthy sex life can alleviate those nasty menstrual cramps that plague women once a month. According to a 2005 article in Redbook, studies have shown that the oxytocin and endorphins released during sex can increase your pain tolerance by up to 70%. That means less pain before her period -- and believe it or not, even during childbirth. Says sex therapist, couples counselor and sex advice columnist Dr. Miro Gudelsky, “Orgasms are one of the best cures for PMS. The reason being that orgasms relieve swelling around the genitals.” No.2: Women get blue balls Or pink balls. Or blue ovaries, as the case may be. Dr. Gudelsky says that “both male and female genitals are made up of erectile tissues that become engorged with blood during sexual excitement. If there is no release during orgasm, there will be much discomfort from all that pressure.” The official fancy medical term? Vasoconstriction. Just because a woman doesn’t necessarily ejaculate doesn’t mean she can’t feel uncomfortable when there’s a lack of release. So next time you start complaining about blue balls, don’t forget she needs to get off, too. No.1: 10-15% of women cannot reach orgasm from intercourse alone Sorry, boys, but it's true. Psychotherapist and author of Cue Cards for Life: Gentle Reminders for Better Relationships, Christina Steinorth, points to a 2009 ABC Primetime report that states that 75% of women need a little help climaxing. Professor of psychology and behavioral neuroendocrinology at Emory University Kim Wallen believes it might have something to do with how far the clitoris is from the vagina. Any more than 2.5 centimeters, and it might be difficult for a woman to achieve orgasm. But Wallen is not the first to research this topic. Turns out Princess Marie Bonaparte, great-grand niece of Napoleon, thought so too, which led her to a series of unfortunate surgeries in the 1920s. All the more reason you should whip out those sex toys and put your tongue and fingers to work.