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Posts Tagged ‘sex’


Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

Biologists may have been building a more nuanced view of sex, but society has yet to catch up. True, more than half a century of activism from members of the lesbian, gay, bisexual and transgender community has softened social attitudes to sexual orientation and gender. Many societies are now comfortable with men and women crossing conventional societal boundaries in their choice of appearance, career and sexual partner. But when it comes to sex, there is still intense social pressure to conform to the binary model.

 

This pressure has meant that people born with clear DSDs (difference/disorder of sex development) often undergo surgery to ‘normalize’ their genitals. Such surgery is controversial because it is usually performed on babies, who are too young to consent, and risks assigning a sex at odds with the child’s ultimate gender identity — their sense of their own gender. Intersex advocacy groups have therefore argued that doctors and parents should at least wait until a child is old enough to communicate their gender identity, which typically manifests around the age of three, or old enough to decide whether they want surgery at all.

 

As many as 1 person in 100 has some form of “DSD” with or without external manifestation. Diagnoses of DSDs previously relied on hormone tests, anatomical inspections and imaging, followed by painstaking tests of one gene at a time. Now, advances in genetic techniques mean that teams can analyze multiple genes at once, aiming straight for a genetic diagnosis and making the process less stressful for families. Children with DSDs are treated by multidisciplinary teams that aim to tailor management and support to each individual and their family, but this usually involves raising a child as male or female even if no surgery is done.

 

The simple scenario that all learn is that two X chromosomes make someone female, and an X and a Y chromosome make someone male. These are simplistic ways of thinking about what is scientifically very complex. Anatomy, hormones, cells, and chromosomes (and also personal identity convictions) are actually not usually aligned with this binary classification.

 

More than 25 genes that affect sex development have now been identified, and they have a wide range of variations that affect people in subtle ways. Many differences aren’t even noticed until incidental medical encounters, such as a forty-six-year-old woman pregnant with her third child, found after amniocentesis that half her cells carry male chromosomes. Or a seventy-year-old father of three who learns during a hernia repair that he has a uterus.

 

Furthermore, scientists now understood that everyone’s body is made up of a patchwork of genetically distinct cells, some of which may have a different sex than the rest. This “mosaicism” can have effects ranging from undetectable to extraordinary, such as “identical” twins of different sexes. An extremely common instance of mosaicism comes from cells passing over the placental barrier during pregnancy. Men often carry female cells from their mothers, and women carry male cells from their sons. Research has shown that these cells remain present for decades, but what effects they have on disease and behavior is an essentially unstudied question.

 

References:

 

https://www.theguardian.com/science/2017/mar/02/cambridge-scientists-create-first-self-developing-embryo-from-stem-cells

 

https://www.ncbi.nlm.nih.gov/pubmed/25693544

 

http://onlinelibrary.wiley.com/doi/10.1002/ajmg.a.34123/abstract;jsessionid=A330AD995EE25C7A0AD5EA478694ADD8.f04t01

 

https://www.ncbi.nlm.nih.gov/pubmed/25091731

 

https://www.ncbi.nlm.nih.gov/pubmed/1695712

 

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Reporter and Curator: Dr. Sudipta Saha, Ph.D.

Disorders of sex development include many different medical conditions. They could happen to anyone, and are actually more common than you might think. You may have heard DSD called terms such as “intersex” or “hermaphrodite” or “pseudohermaphroditism.” However, a meeting of international experts reached consensus that the term “disorders of sex development” should replace those terms. Because there are so many stages of sex development in human life, there are a lot of opportunities for a person to develop along a path that is not the average one for a boy or a girl. When a less-common path of sex development is taken, the condition is often called a “disorder of sex development” or DSD. So DSD is a name given to a lot of different variations of sex development.

These conditions have specific names, and include:

  • 46,XX congenital adrenal hyperplasia (CAH)
  • Testosterone biosynthetic defects
  • Androgen insensitivity syndrome (AIS)—can be partial (PAIS) or complete (CAIS)
  • Gonadal dysgenesis (partial and complete)
  • Swyer syndrome (46,XY gonadal dysgenesis)
  • 5-alpha reductase deficiency (5-AR deficiency)
  • 46,XY micropenis
  • Klinefelter syndrome (47,XXY)
  • Turner syndrome (45,X)
  • Hypospadias
  • Epispadias
  • Mayer-Rokitansky-Kuster-Hauser syndrome (Also called MRKH, Müllerian agenesis and vaginal agenesis)
  • Sex-chromosome mosaicism (for example mixed gonadal dysgenesis (45,X/46,XY; sometimes referred to as XY Turners)
  • 46,XX/46,XY (chimeric, ovotesticular DSD)
  • Persistant Müllerian duct syndrome
  • Kallman syndrome
  • 17-beta reductase deficiency (XX or XY)
  • 46,XY 3-beta-hydroxysteroid dehydrogenase deficiency (HSD deficiency)
  • Aphallia
  • Clitoromegaly
  • 46,XY cloacal exstrophy
  • Progestin-induced virilization

The symptoms associated with intersex will depend on the underlying cause, but may include:

  • Ambiguous genitalia at birth
  • Micropenis
  • Clitoromegaly (an enlarged clitoris)
  • Partial labial fusion
  • Apparently undescended testes (which may turn out to be ovaries) in boys
  • Labial or inguinal (groin) masses — which may turn out to be testes — in girls
  • Hypospadias [the opening of the penis is somewhere other than at the tip; in females, the urethra (urine canal) opens into the vagina]
  • Otherwise unusual appearing genitalia at birth
  • Electrolyte abnormalities
  • Delayed or absent puberty
  • Unexpected changes at puberty

Disorders of sex development (DSD) with or without ambiguous genitalia require medical attention to reach a definite diagnosis. Advances in identification of molecular causes of abnormal sex, heightened awareness of ethical issues and this necessitated a re-evaluation of nomenclature. The term DSD was proposed for congenital conditions in which chromosomal, gonadal or anatomical sex is atypical. In general, factors influencing sex determination are transcriptional regulators, whereas factors important for sex differentiation are secreted hormones and their receptors.The current intense debate on the management of patients with intersexuality and related conditions focus on four major issues: 1) aetiological diagnosis, 2) assignment of gender, 3) indication for and timing of genital surgery, 4) the disclosure of medical information to the patient and his/her parents. The psychological and social implications of gender assignment require a multidisciplinary approach and a team which includes ageneticist, neonatologist, endocrinologist, gynaecologist, psychiatrist, surgeon and a social worker. Each patient should be evaluated individually by multidisciplinary approach.

Source References:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3184510/

http://en.wikipedia.org/wiki/Disorders_of_sex_development

http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002634/

http://www.med.umich.edu/yourchild/topics/dsd.htm

http://www.accordalliance.org/dsd-guidelines.html

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Women

 

Author: Jukka Karjalainen, MD, PhD

 

Sorry ladies, you will be seduced, pheromones make it impossible for you to resist men, no matter how dreadful the man wearing the pheromones may be.

Wait, please don’t panic. Sadly, the pheromone marketing craze may be causing us to turn a blind eye to an interesting discovery. As far as I see it’s like hearing about vitamins for the first time from a hard core drug dealer. When you get over your encounter with Mr. Dealer, you are not going to think of vitamins in the same way as a person who had heard about vitamins from GNC or Vitamin World. I believe the same thing is happening with marketers and pheromones. With that in mind let’s take a deeper look at pheromones.
Most people still believe pheromones are no different from X-ray glasses sold in the back of comic books. Some have been using them for years. To be sure, they are used heavily by government agencies worldwide. Business uses them daily, you may even use them. Of course I’m talking about insect and animal pheromones.
It was well known by the late 70s that females of the insect and animal kingdom produced chemicals for attracting males of the same species. Several examples were presented in literature. By the late 70s pheromones were already being manufactured for pest control. Indeed, pheromones were being used to attract or repel bugs and animals. Pheromones were already protecting crops from damage. Roaches were checking in and not checking out. At the same time scientist were working hard to find and prove the existence of human pheromones. This evidence was found in the mid 70s but did not reach the public with any power until the mid 80s.

Human pheromones made front page news in 1986 when Researchers at the Monell Chemical Senses Center of Philadelphia released their findings to the scientific journal Hormones and Behavior, as well as to the public by way of:

  • Time Magazine: “Studies find that male pheromones are good for women’s health.”
  • News week: “The Chemistry Between People: Are Our Bodies Affected by Another Person’s Scent?”
  • USA Today: “The Real Chemical Reaction between the Sexes.”
  • The Washington post: “Pheromones Discovered in Humans.”

The human pheromone was big news in the 80s. It was found that women’s health was directly affected by male pheromone. Interestingly, Monell Chemical Senses Center of Philadelphia reported that women who work or live together tend to get their menstrual cycles in sync. That curious phenomenon known for years by scientists and many ordinary folk, has long been suspected as an indication that humans, like insects and some mammals, communicate subtly by sexual aromas known as pheromones. (1)

In 1986 Dr. Winnifred Cutler, a biologist and behavioral endocrinologist, co discovered pheromones in our underarms. She and her team of researchers found that once any overbearing underarm sweat was removed, what remained were the odorless materials containing the pheromones. The approach to test the hypothesis was interesting: women and men emitted pheromones into the atmosphere and the authors showed that extracted pheromones could be collected, frozen for over a year, thawed and then applied topically above the upper lip of recipients to mimic some of the pheromonal effects found in nature. Dr. Cutler’s original studies in the ’70s showed that women who have regular sex with men have more regular menstrual cycles than women who have sporadic sex. Regular sex delayed the decline of estrogen and made women more fertile. This led the research team to look for what the man was providing in the equation. By 1986 they realized it was pheromones. (1, 2, 3).
Male scents play a role in maintaining the health of women, particularly the health of the female reproductive system. Pheromones help to maintain the health of women. To be more exact, they keep a woman’s reproductive system healthy. They found that women who have sex with men at least once a week are more likely to have normal menstrual cycles, fewer infertility problems and a milder menopause than celibate women and women who have sex rarely or sporadically. A healthy testosterone rich male pheromone signature somehow encouraged a woman’s body to keep itself healthy and young.

The scent of a good man may be music to a woman’s nose. Researchers also found that exposure to the male pheromones also prompted a shift in blood levels of a reproductive hormone called luteinizing hormone (LH). Levels of this hormone typically surge before ovulation, but women also experience small surges during other times in the menstrual cycle. It also can stabilize the menstrual cycle and reduce the symptoms of PMS. Pheromones could lift a woman’s mood actually alleviating depression, even postpone and then alleviate menopause health. (1, 2)
How did we get from health benefits to wild seduction products? People can’t resist a fast buck. If it’s about money, maybe we should be using pheromone products to make women’s lives better. Strike that. We should instead be using pheromone products to make people’s lives better. Provide pheromones that do the things mentioned above. Help to enable pheromone research that will gain more knowledge related to health and longevity. I don’t have anything against attracting the opposite sex. I think that’s a good idea. It’s just sad to see a good thing, or potentially good thing, be lost because of a poorly focus on health.

There is always more to the story than meets the eye. The person who does not ask questions has either been beaten down low by the people who know-it-all, or, they are the people who know-it-all. Keep asking questions. You will keep finding better answers.

REFERENCES: 
1. Biology of Reproduction, June 2003. News release, University of Pennsylvania.
2. Cutler WB, Preti G, Krieger A, Huggins GR, Garcia GR, Lawley HJ. Human axillary secretions influence women’s menstrual cycles: the role of donor extract of men. Horm Behav 1986; 20: 463473.
3. McCoy and Pitino. Pheromonal influences on sociosexual behavior in young women. Physiology & Behavior 2002; 75: 367-375.

 

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Reported by: Dr. Venkat S Karra, Ph.D.

Two-thirds of Americans aged 15 to 24 have engaged in oral sex, according to a broad new survey of young people’s sexual habits.

The data, published Aug. 16 in the U.S. Centers for Disease Control and Prevention’s National Health Statistics Reports, also reveals that about one-quarter of young people try oral sex before they engage in intercourse.

“I don’t think these numbers are surprising, but I do think that it’s important that this data has been captured at all, because it’s really important to have, and has for a long time been a fuzzy area in our understanding of sexual behavior,” said one expert, Dr. Christopher Hurt, A clinical assistant professor in the division of infectious disease at the University of North Carolina.

He said the findings are also valuable because too many people of all ages mistakenly believe that oral sex is “risk-free.”

“That’s not the case,” Hurt said. “Studies looking, for example, at patients visiting STD [sexually transmitted disease] clinics have shown that 5 to 10 percent have gonorrhea in the throat. And it’s often asymptomatic and can be transmitted through oral sex.”

Gonorrhea is becoming increasingly resistant to antibiotics, and a report released last week by the CDC noted that certain strains are resistant to all but one such drug. Oral sex can also raise risks for infection with chlamydia, herpes and syphilis, the CDC noted.

Oral sex is also increasingly linked to transmission of the human papillomavirus (HPV), which may be linked to cancers of the throat and oral cavity, in addition to cervical cancer, experts say.

While the odds of contracting any sexually transmitted disease from oral sex remain lower than that for unprotected intercourse, the CDC has stated that “numerous studies have demonstrated that oral sex can result in the transmission of HIV and other sexually transmitted diseases.”

The new report is based on data from the agency’s seventh National Survey of Family Growth, involving interviews conducted between 2007 and 2010 with nearly 22,700 people between the ages of 15 and 44.

Even though the survey found that about one-quarter of Americans aged 15 to 24 engaged in oral sex before they moved on to intercourse, for about another quarter of respondents the opposite was true — they tried penile-vaginal intercourse prior to engaging in oral sex. Among males, 12 percent said their first experience with both practices occurred at the same time, while a little more than 7 percent of women said that that was the case for them.

Examining behaviors solely among the youngest participants — those 15 to 19 years old — the CDC team found that more than half of American girls and boys in this age group had already engaged in some form of sexual contact with someone of the opposite sex (55 percent of girls and 58 percent of boys).

Among the survey’s other findings:

  • About 5 percent of women and nearly 7 percent of men aged 15 to 24 said that at the time of the survey they had only engaged in oral sex, not intercourse. Another 28 percent of women and nearly 29 percent of men said they had had no sexual experiences with an opposite-sex partner whatsoever.
  • Among girls aged 15 to 19 years, oral sex and vaginal intercourse experience were equally common (48 percent and 47 percent, respectively), while among similarly aged boys oral sex was slightly more common (49 percent) compared to intercourse (44 percent).
  • Rates of sexual behaviors did not appear to vary widely by race. For example, among females aged 15 to 24, nearly three-quarters (74 percent) of black women, 68 percent of Hispanic women and 66 percent of white women said they had had vaginal intercourse.
  • Among males aged 15 to 24, about seven in 10 black and Hispanic men said they had had intercourse, compared with 63 percent of white men. There were no appreciable racial differences observed in terms of the percentages of those who said they had engaged in oral sex, the CDC survey found.

According to Hurt, young people need to be properly armed with knowledge before they engage in their first sexual activity, and that includes information on the risks that accompany oral sex.

“I would say that the risk of STD transmission through oral sex is underappreciated and underestimated,” he said. “As part of sex education programs, kids need to be made aware of that fact: that oral sex is not a completely risk-free activity.”

SOURCES: Christopher Hurt, M.D., clinical assistant professor, division of infectious diseases, University of North Carolina, Chapel Hill; Aug. 16, 2012, U.S. Centers for Disease Control and Prevention’s National Center for Health Statistics report, Prevalence and Timing of Oral Sex with Opposite-Sex Partners Among Females and Males Aged 15-24 Years: United States: 2007-2010

Source

http://www.nlm.nih.gov/medlineplus/news/fullstory_128320.html

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