Some women will want to string me up for this one. I'm about to divulge some of the real reasons a gal will say "no" to sex, even if she's totally in the mood.

There are plenty of them. They're very human. They're all too common. But most are hardly ever uttered because they're not sexy. Many, however, are easily squelched with the right remedy. So know that the next time she says, "I have a headache," you've got her code cracked in being up on the following ...

1. She feels fat.

Whether post-dinner or every minute of the day, when a woman feels heavy, she's not exactly making a beeline for the bedroom. She'd rather hide under a rock than act like a rock star in the sack. The tragedy is that she needs that loving touch more than ever when she gets down about her shape. Verbal and physical reassurances let her know that she's cared for, desirable, and loved. The more you put out positive energy, the likelier she'll invite you in.

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2. She's feels gassy.

That's right. Women toot too. And whether she sounds like a trumpet or is being held hostage by a battle of bad gas, she's feeling like a walking fart pillow. Even when she wants your touch, if her cherry bomb self feels more like a bloated whale than babe, nobody is seeing any action. This is definitely one of those proceed-at-your-own-risk situations.

3. She has her period.

While some couples have absolutely no qualms about sex during the week of a woman's period, some aren't into it. That time of the month may be your monthly time out when it comes to sexual intimacy. Other than missed opportunities to connect, the real shame in this is that sex prior to and during menstruation eases menstrual cramps and pelvic congestion. Some women also feel their sex drive go into high gear during their period. Possible reasons for this: increased pelvic congestion and decreased risk of pregnancy. Any of these benefits may serve either of you well in getting over this bodily function as a barrier to more sex.

4. She's wearing grandma underwear.

The original bare necessity resembled more of a parachute than dental floss. And in the age of g-strings, it's easy to forget that grandma underwear can be quite functional. Involuntarily or not, every now and then, a woman may need a break from her thong. This is often related to where she's at in her menstrual cycle or if she's dealing with a sexual health ailment. While there are no scientific studies confirming a link between wearing a thong and getting a UTI (urinary tract infection) or yeast infection, many gynecologists are noticing increasing recurrent cases among thong wearers. All in all, the grandmas are not going to have her feeling like a femme fatale. Your best bet, if she's got an A+ in the sexual health department, is to encourage her to get out of her clothes privately before getting all over her yourself.

5. She has a yeast infection.

Sorry, but I'm going there. If she has a yeast infection, and if she's on an antifungal medication, then there's no way you're touching her for the next few days. Yeast infections can be due to a number of reasons and are basically when the healthy yeast that always exist in her reproductive system gets thrown out of balance. There's nothing wrong with them. It's just that they're a total inconvenience and definite buzz kill in the boudoir. When it comes to unprotected sex, the yeast can be transferred from one partner to the other. Partners can then end up re-infecting each other if they do not take a break from sexual intercourse during treatment.

6. She's sweaty or unclean.

While sweaty sex can be heat-inducing for some couples, a number of women have trouble embracing sexual intimacy if they need a shower. Even when her system is revved up post-workout, if she feels funky "down there," hasn't shaved her legs for days, or is fretting over body odor, no one is seeing any action. So make sure that foreplay involves a shower or bath. You'll be good to go from there ...

7. Neither of you brought a condom.

Despite high unplanned pregnancy rates, there are people who practice planned parenting. So if neither of you brought birth control and she's worried about getting pregnant, then game over. Better luck next time.

8. Her parents – or yours – are too close for comfort.

There are times when she wants sex like there's no tomorrow, but if she's under any parents’ roof, she's going to revert back to her pre-teen abstinent self. Besides the noise factor, many women will have trouble letting go knowing that privacy is not absolute. This goes for having kids within earshot as well.

9. Her nether region feels dry.

A woman's lubrication can change throughout her menstrual cycle and throughout her lifetime. This can leave her feeling a bit frustrated that she's not responding the way she wants to, despite a raging libido. Fortunately, there are plenty of lubes out there that can nip this problem in the bud.

10. She's tired.

A lot of women can actually have some of their sweetest sexual moments when tired, if they would just allow for it. With the body totally relaxed, she may find herself more receptive to touch and stimulation. Her body may respond more easily in reaching climax. Believe me.

11. She's already taken care of business.

Sometimes a lady has to take matters into her own hands. So if she's beaten you to the punch, she may need a little convincing that a round two is worth her time. Let's not forget, however, that, unlike a male, a woman can be catapulted into the sexual response cycle soon after climax.

12. She's ticked off at you.

Even if you're making her all hot 'n' bothered, if you've done anything to tick her off, then she's going to punish both of you. The good news, though, is that once you kiss and make up, the sex should be super hot.

13. She's grossed out by your lack of hygiene.

You might feel like a stud after a hard day on the job or working in the yard. But she's thinking you stink. She's not going to touch you with a 10-foot pole until every part of you has been thoroughly washed and clean. This is a case where a man wants to smell like roses.

14. She's waiting for her wedding day.

Whether she can still claim virginity status or has decided to practice secondary abstinence until she's at the altar, if she's set on waiting till she's wed, you will be too. Don't even try to push this one: Couples who take a break from sleeping together prior to their Big Day claim that the temporary torture is well worth it.

15. She's pregnant and feels guilty for it.

Despite untamable hormones, if a woman has bought into the urban legend that "preggie isn't sexy," then she's not going to embrace her new "with child" sex symbol status. So become her personal maiesiophiliac -- a person whose object of obsession is a woman who is or appears pregnant. Letting her know how incredibly sensual and sexual she is may help draw her out of her shell.

In the Know Sex News:

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Malaysian Minister Defends School Uniform. In light of complaints that government school uniforms for girls are too "sexy," Malaysia's education minister is rejecting suggestions that the white blouse with a blue skirt garb encourages rape and premarital sex. A Malaysian Islamic group has found it too transparent and "a distraction to men."

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Dr. Yvonne Kristín Fulbright is a sex educator, relationship expert, columnist and founder of Sexuality Source Inc. She is the author of several books including, "Touch Me There! A Hands-On Guide to Your Orgasmic Hot Spots."

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