Myth: A women can't get pregnant during her period.

While a woman is unlikely to conceive during menstruation, "nothing, when it comes to pregnancy, is impossible," said Aaron Carroll of Indiana University and co-author of "Don't Swallow Your Gum: Myths, Half-truths and Outright Lies About Your Body and Health" （St. Martin's Griffin, 2009）.

Once inside a woman, sperm can wait for an egg for up to a week. Ovulation can occur soon after, or even during, the bleeding phase of a woman's menstrual cycle, giving patient sperm the chance to get lucky. The timing method of birth control doesn't work well, Carroll said, agreeing that couples who practice it are often called: parents.

Myth: Menopause causes sex drive to nosedive.

The Change is not necessarily one that happens in the bedroom. A comprehensive survey of sexual habits in the United States, completed by Edward Laumann and colleagues in 1994, found that roughly half of women in their fifties have sex several times a month.

While hot flashes and other discomforts may make a women temporarily not in the mood, there is not a direct link between menopause and sexual desire, Vreeman said. So if you are entering the Big M, there is no reason to say good-bye to the Big O.

Myth: Antibiotics make birth control pills unreliable.

"Many physicians even believe this," Carroll said. Alone, birth control pills fail about one percent of the time. And that failure rate is unchanged when taken with the vast majority of antibiotics, Carroll said.

A possible exception is rifampin, the antibiotic prescribed for tuberculosis. Rifampin does lower pregnancy-protecting hormone levels induced by birth control pills, but whether the effect is large enough to increase pregnancy risk is unclear. Carroll thinks rifampin research spurred the antibiotic/birth control rumor. "Sometimes people say things and they just take off," he said.

Myth: Women and men need equal sleep.

Tossing and turning not only causes women more psychological distress, it also raises their insulin and inflammation levels -- risk factors for compromised health, found a 2008 study of 210 people led by Edward Suarez at Duke University.

A study of more than 6,000 participants, led by researchers at the University of Warwick in 2007, found that women who slept five or less hours a night were twice as likely to suffer from hypertension than women who slept for seven or more hours. Among men, there was no such relationship. Sleeping Beauty may be better off waking up on her own watch.

Myth: A doctor can tell if a woman is a virgin.

Even when using 10-fold magnification, doctors can not accurately sort virgins from the sexually-active, several studies have reported. It is not as simple as looking for a hole in the hymen because, well, there is always a hole in the hymen.

"Some people think the hymen seals off the vagina [until virginity is lost], but that is just not true," said Dr. Rachel Vreeman of Indiana University and Carroll's co-author of "Don't Swallow Your Gum." In the rare cases when it is sealed, period blood builds in the uterus and causes severe medical problems, she said.

误区：女性在月经期间不能怀孕

虽然女性在经期不太可能怀孕，但印第安那州大学的埃伦。卡罗说："说到怀孕，一切皆有可能。"同时，他也合写过"别吞口香糖： 对你的身体和健康荒诞，半真半假的说法甚至是十足的谎言".（圣。 马丁格里芬出版社，2009）

一旦精子进入了女性的身体， 它能存活长达一周的时间来与卵细胞结合。排卵可能在女性月经周期结束后发生， 也可能在经期内排血的阶段发生， 使得耐心等候的精子就有机会与卵细胞结合。 计算安全期的方法并不能有效地避孕，卡罗说道。 同时他认为那些使用这种方法来避孕的夫妻很可能会成为父母。

误区： 更年期是性欲的杀手

这种改变并不一定是卧室里发生的那种改变。 1944年，由爱德华。劳曼和他的同事一起完成的关于美国人性习惯的全面的调查显示， 五十多岁的女性中大约有一半的人一个月会有好几次性生活。

热潮红和其他方面的不适可能会使女性暂时的心情不适因而不想进行性生活，所以更年期和性欲并没有之间的关联， 弗尔曼说。 所以当你进入更年期，你不必和性快乐说拜拜。

误区： 服用抗生素导致避孕药失效

"甚至许多医生都相信这个说法。" 卡罗说。 单单吃避孕药的话， 失败率大约1%. 而当你在吃避孕药的同时， 还服用大多数种类的抗生素时， 失败率还是1%.

可能的例外就是利福平，这种抗生素是专为治疗肺结核研制的。利福平确实会降低服用避孕药所产生的适合怀孕的荷尔蒙含量， 但是这种反应是否大到可以影响怀孕机率的程度还不知晓。 卡罗认为利福平的研究使得人们越来越相信抗生素使避孕药失效的谣言。 " 有时，人们讲话，讲完了就不管了。" 他说

误区： 女性与男性需要相同时间的睡眠。

辗转反侧不仅使女性在心里上感到不安愁闷，还会提高她们体内的胰岛素的含量以及容易发生炎症-这些会危害健康。 这是由德克大学的爱德华。苏瑞在2008年通过对210人进行研究发现的。

2007年，沃里克大学的研究者对6000多人进行研究发现晚上睡眠为5小时或更少的女性得高血压的可能性是比那些睡7个小时或更多的女性的两倍。而在男性中，没有这种比例关系。

睡美人最好按自己的生物钟起床。

误区：医生可以分辨出你是否是处女。

即使医生使用十倍的放大器材，他们还是不能精确地将处女与性经验丰富的女性区分开来，好几个研究都报导过。这并不是简简单单地寻找处女膜上是否有洞，因为处女膜上总是会有洞的。

"有人认为处女膜将阴道封住了（直到丧失了贞操）,但这是不对的。"印第安那州大学的博士瑞秋。弗尔曼说。 同时他和卡罗一起合写了 "别吞口香糖". 这样的例子很少，当它被封住时，经血会涌入子宫， 而且会造成严重的疾病， 她说。