芜湖到无为高铁站多久:女性身体的认识误区－希波克拉底王的博客 - 丁香博客

女性身体的认识误区

历史上大多数的医学健康研究都是基于男性身体完成的，直到最近几年，女性的身体才得到了越来越多的关注。大家千万不要以为是因为性别歧视造成了针对男性的研究多于女性，而对科学界加以指责。事实上，相比男性荷尔蒙，女性荷尔蒙不够稳定，而且结构更加复杂，有可能对基础研究带来很大的困扰。也正是因为如此，我们对于女性身体还有更多认识误区，本文将一一揭开这些秘密。
 

误区1：在经期内进行性生活不会怀孕

尽管经期内的性生活使女性怀孕的概率很低，“但是，对怀孕而言，没有什么不可能发生，”美国印第安纳州立大学的Aaron Carroll说，他是《别吞下你的口香糖：有关你身体和健康的谎言和迷思》（Don't Swallow Your Gum: Myths, Half-truths and Outright Lies About Your Body and Health）一书的作者。

在女性体内，精子的存活期可长达一周，等待着卵子的到来。经期刚过，排卵就会发生，排卵过程甚至有时候会发生在这烦人的经期之内，这样一来，那些有足够耐心的精子就有机会和卵子结合，导致怀孕。因此，通过计算时间来避免怀孕的方法不会总是奏效，Carroll说，如果经常在这一时间内不加其他避孕措施进行性生活，那么，怀孕就有可能发生。

误区2：更年期会使得性欲急剧下降

这并不是性生活发展的一个必然趋势。早在1994年，Edward Laumann就在美国进行了一项关于性生活习惯的大面积普查，调查结果显示，在年龄超过50岁的妇女中，仍有一半的人每个月都会进行数次性生活。

尽管部分更年期妇女会有潮热（hot flash）或其他不适症状，但这并不代表性欲和更年期有必然联系，Vreeman说。所以，如果你还能享受性生活带来的快乐，就没有理由对它说再见。

误区3：抗生素将使避孕药失效

“很多内科医生都相信（抗生素将使避孕药失效），”Carroll说。避孕药失效的概率只有1%左右，即使你服用了大量抗生素，也不会影响这一概率，Carroll补充到。

利福平（rifampin，甲哌力复霉素）是一个例外，这是一种治疗肺结核的处方药。利福平会降低避孕药释放出的防止怀孕的荷尔蒙的水平。Carroll认为，正式利福平引起了有关抗生素会使避孕药物失效的传闻。他说：“人们现在刚脱下衣服就开始想这个问题。”

误区4：女性和男性需要同样的睡眠时间

美国杜克大学的Edward Suarez在2008年对210人进行了一次系统研究，他发现女性更容易失眠或者惊醒，这将导致女性患心理疾病的概率增大，同时还会导致胰岛素水平上升，并出现更多的炎症——这些都将损害人的健康。

英国华威大学的一个研究项目，参与者超过6,000人。对这6,000多人的研究调查表明，每天睡眠不足5小时的女性患高血压的可能性是每天睡眠7小时以上女性的2倍。对男性而言，却没有这样的关系。研究认为，更多的睡眠将使女人更健康。

误区5：医生可以检查出一个女人是不是处女

数项研究表明，即使给医生放大倍数再大上10倍的放大镜，他们也无法准确判断一个女孩是不是处女。这项工作并非大家想象的那样，就是在处女膜上找一个洞那么简单。事实上，处女膜上本来就有一个洞的。

Rachel Vreeman是美国印第安纳州立大学教授，同时也是《别吞下你的口香糖》一书的合著者（另一位作者是Carroll），她说：“一些人认为（在一个女人失去贞操之前），处女膜是将阴道封闭起来的，其实这是错误的观念。”她继续说，只在极少的个案中，处女膜将阴道封闭起来，这样一来，女性经血将无法排出，进而引发多种疾病。

（Scientific American）

【原文】5 Myths About Women's Bodies

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.