Sexual Health
Low fertility in Europe—is there still reason to worry?
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The post-war trend of falling birth rates has been reversed across Europe, according to a new study. However, despite an increasing emphasis on family and fertility policies in Europe, this recent development involves social, cultural and economic factors more than individual policy interventions.
For some decades, couples have been having children later in life. But birth-rates among younger women have stabilised and the long-term trend towards lower fertility rates has been reversed.
Politicians are still left to grapple with problems associated with an ageing population as Europeans live longer and birth rates remain below the level needed to dramatically change the balance between young and older people.
Cell phone use may reduce male fertility
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Men who have been diagnosed with poor sperm quality and who are trying to have children should limit their cell phone use. Researchers have found that while cell phone use appears to increase the level of testosterone circulating in the body, it may also lead to low sperm quality and a decrease in fertility.
“Our findings were a little bit puzzling,” says Rany Shamloul, a postdoctoral fellow in the Department of Pharmacology and Toxicology and lead researcher on the project. “We were expecting to find different results, but the results we did find suggest that there could be some intriguing mechanisms at work.”
The research team discovered that men who reported cell phone use had higher levels of circulating testosterone but they also had lower levels of luteinizing hormone (LH), an important reproductive hormone that is secreted by the pituitary gland in the brain.
Childhood sexual abuse may be a risk factor for later psychotic illness
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An Australian study suggests that children who are sexually abused, especially if it involves penetration, appear to be at higher risk for developing schizophrenia and other psychotic disorders, according to a report in the November issue of Archives of General Psychiatry, one of the JAMA/Archives journals. Previous studies have established that abused children are more likely to develop depression, anxiety, substance abuse, borderline personality disorders, posttraumatic stress disorder and suicidal behavior, according to background information in the article. “The possibility of a link between childhood sexual abuse and later psychotic disorders, however, remains unresolved despite the claims of some that a causal link has been established to schizophrenia,” the authors write
Margaret C. Cutajar, D.Psych., M.A.P.S., of Monash University, Victoria, Australia, and colleagues linked data from police and medical examinations of sexual abuse cases to a statewide register of psychiatric cases. Rates of psychiatric disorders among 2,759 individuals who had been sexually abused when younger than age 16 were compared with those among 4,938 individuals in a comparison group drawn from electoral records.
Over a 30-year period, individuals who had experienced childhood sexual abuse had significantly higher rates than those in the comparison group of psychosis overall (2.8 percent vs. 1.4 percent) and schizophrenia disorders (1.9 percent vs. 0.7 percent).
Researchers visualize herpes virus’ tactical maneuver
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For the first time, researchers have developed a 3D picture of a herpes virus protein interacting with a key part of the human cellular machinery, enhancing our understanding of how it hijacks human cells to spread infection and opening up new possibilities for stepping in to prevent or treat infection. This discovery uncovers one of the many tactical manoeuvres employed by the virus.
The Biotechnology and Biological Sciences Research Council (BBSRC)-funded team, led by The University of Manchester, have used NMR - a technique related to the one used in MRI body scanners and capable of visualising molecules at the smallest scales – to produce images of a herpes virus protein interacting with a mouse cellular protein. These images were then used to develop a 3D model of this herpes virus protein interacting with human protein. The research is published this evening (06 January) in PLoS Pathogens.
Lead researcher Dr Alexander Golovanov from Manchester’s Interdisciplinary Biocentre and Faculty of Life Sciences said “There are quite a few types of herpes viruses that cause problems as mild as cold sores through to some quite serious illnesses, such as shingles or even cancer. Viruses cannot survive or replicate on their own – they need the resources and apparatus within a human cell to do so. To prevent or treat diseases caused by viruses we need to know as much as possible about how they do this so that we can spot weak points or take out key tactical manoeuvres.”
Viagra-popping seniors lead the pack for STDs
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Even if you’re past your prime and have a hard time getting an erection, you might still need to worry about unprotected sex, according to U.S. doctors.
In fact, they report in the Annals of Internal Medicine, the rate of sexually transmitted diseases (STDs) in older men taking erectile dysfunction drugs like Viagra is twice as high as in their non-medicated peers.
In both groups, however, the numbers are swelling. According to the Centers for Disease Control and Prevention, there were more than six new cases of STDs per 10,000 men over 40 in 2008, up almost 50 percent since 1996.
Banning all gay men from donating blood is unscientific and wrong, say AIDS research pioneers
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Since 1983, blood agencies in Canada, the United States and many other industrialized nations have disallowed all blood donations from men who have sex with men (MSM.) While a total ban was justified scientifically and ethically in 1983, in 2010 it no longer makes sense, say pioneering AIDS researchers Dr. Mark Wainberg and Dr. Norbert Gilmore in an article to be published May 25 in the Canadian Medical Association Journal (CMAJ.)
Dr. Wainberg heads the HIV research program at the Lady Davis Institute for Medical Research (LDI) at the Jewish General Hospital and was a co-discoverer of 3TC, one of the first drugs known to control HIV. He also heads the McGill University AIDS Centre, based at the LDI. Dr. Norbert Gilmore is a professor at the McGill Faculty of Medicine and the McGill Centre for Medicine, Ethics and Law, and is a clinician at the McGill University Health Centre (MUHC.)
“The 1983 ban has hung on so long, unfortunately, because many people became infected by HIV in the early 80s through blood transfusions, and they have mounted continuing pressure on the blood agencies to maintain the ban,” says Wainberg. “While we can sympathize with them, this no longer makes sense in 2010, and with each passing year it makes less sense.”
New study links masturbation and prostate cancer
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Given the bind that many prominent American men have thrust themselves into — think Tiger Woods, Mark Sanford, Eliot Spitzer, et al. — it seems it really is possible to have too much of a good thing. And your prostate gland appears to agree.
According to a new research out of the UK, men who have frequent sex in their twenties and thirties were at a greater risk of developing prostate cancer later in life. What’s even more unusual is that researchers showed that young men who masturbated frequently, as opposed to those who have sex frequently with a partner, were at an even greater risk of developing prostate cancer.
Substance abuse diagnostic test for teens can also predict high risk sexual behavior
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Alcohol and drug use are known contributors to adolescents engaging in dangerous sexual activity; leading to substantial health risks such as unwanted pregnancies, sexually transmitted illnesses, drug overdoses and alcohol poisonings. Yet, research suggests that fewer than half of pediatricians report screening patients for substance use and at-risk sexual behavior. CRAFFT, the diagnostic test developed and currently being employed at Children’s Hospital Boston, allows primary care physicians to accurately screen teens for high risk drug and alcohol use in a matter of minutes. Now, according to a new study appearing in the Journal of Adolescent Health, Children’s researchers have established that the CRAFFT diagnostic test can also identify teens that are more likely to be engaging in high risk sexual behaviors.
The studies researchers found that teens who screened positive for substance use had significantly greater odds of having sexual contact after using drugs or alcohol. According to the findings, these teens were more likely to have unprotected sex, multiple sexual partners and even a sexually transmitted illness.
The cross-sectional survey consisted of 305 adolescents from ages 12- to 18-years-old in 3 different urban clinics. Participants were asked the CRAFFT questions, and also completed a self-administered questionnaire about high risk sexual behaviors. Of those who screened positive, 42.6% reported having sexual contact without a condom, 26.1% after drinking alcohol, 15.6% after drug use and 21.7% with a partner who had been drinking alcohol.
Estrogen link in male aggression sheds new light on sex-specific behaviors
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Territorial behavior in male mice might be linked to more “girl-power” than ever suspected, according to new findings at UCSF. For the first time, researchers have identified networks of nerve cells in the brain that are associated with how male mice defend their territory and have shown that these cells are controlled by the female hormone estrogen.
The research suggests a pivotal role for estrogen – as well as the enzyme aromatase that is responsible for estrogen synthesis – in male territorial behavior, according to findings published in the October 2, 2009 issue of the journal Cell. The paper, based on research at UCSF and Fujita Health University, also appears online at http://www.cell.com.
Estrogen’s role in the mating behaviors of these mice, however, was less clear, which indicates that territorial and sexual behaviors are likely influenced by distinct and separate connections in the brain, according to Nirao Shah, MD, PhD, an assistant professor in the UCSF Department of Anatomy and senior author of the paper.
Vietnam birth trend may fuel sex work, trafficking
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The ratio of boys born in Vietnam compared with girls has grown at an unusually rapid pace in recent years and could lead to a rise in sex work and trafficking, the United Nations said.
The sex ratio at birth was 112.1 male births per 100 female births in 2008, up from an estimated 106.2 in 2000, the U.N. Population Fund (UNFPA) said in a report.
With growth since 2006 of one percentage point per year, the ratio might cross the 115 mark within three years, it said.
Spread your sperm the smart way
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Attractive males release fewer sperm per mating to maximise their chances of producing offspring across a range of females, according to a new paper on the evolution of ejaculation strategies. The findings by researchers at UCL (University College London) and the University of Oxford suggest that, paradoxically, matings with attractive males may be less fertile than those with unattractive ones.
In a paper to be published in the journal American Naturalist, the team mathematically modelled a range of male ejaculation strategies to look for the optimum “sperm load” per mating, and how this might vary depending on mating patterns. Previous studies have shown that in animals such as the domestic fowl, and fish such as the Arctic charr, males with privileged access to females produce ejaculates of lower fertilising quality than subordinate males.
Sam Tazzyman, UCL CoMPLEX (Centre for Mathematics and Physics in the Life Sciences and Experimental Biology), says: “In some species, females mate with many different males. Each male’s sperm competes with that of other males in a process known as ‘sperm competition’. Since males have finite resources to allocate to breeding, they allocate them carefully to each mating to maximise their number of offspring. If a male puts a lot of resources into each mating he will get more offspring per mating, but at the expense of fewer matings. If, on the other hand, a male puts few resources into each mating he will secure less paternity per mating, but will be able to carry out more matings overall. Thus, there is a trade-off between number of matings and success per mating.”
China shuts sex health websites to ordinary users
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Ordinary web users in China will be banned from surfing sex-related medical and research websites from next month, amid an Internet crackdown on pornographic online content, according to new regulations.
Medical information service providers must install software to ensure only professionals can access sites that carry information and research about sex, the regulations on the website of the Ministry of Health (http://www.moh.gov.cn) said.
“It is prohibited to spread pornographic content in the name of sex-related scientific research,” the regulations said.
Cher struggles, but supports child’s sex change
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Cher has struggled to understand her child’s decision to have a sex change operation but remains supportive and respectful of the courage it takes, the pop star said in a statement on Thursday.
Formerly Chastity Bono, the 40-year-old is the child of Cher and Sonny Bono and now goes by the name Chaz Bono. Chaz has begun operations and hormone treatments to become a man.
“Chaz is embarking on a difficult journey, but one that I will support,” Cher, 63, said in a statement to People magazine and other celebrity media outlets.
Depression Medications May Reduce Male Fertility
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As many as half of all men taking the antidepressant medication paroxetine (trade names Seroxat, Paxil) may have increased sperm DNA fragmentation—a predictor of compromised fertility. Research led by NewYork-Presbyterian Hospital/Weill Cornell Medical Center also found that the changes are reversible with normal levels of sperm returning after discontinuation of the drug.
The study is currently published in the online edition of the journal Fertility & Sterility, and represents one of the first scientific investigations into the effect of antidepressants on sperm quality.
“It’s fairly well known that SSRI antidepressants negatively impact erectile function and ejaculation. This study goes one step further, demonstrating that they can cause a major increase in genetic damage to sperm,” says Dr. Peter Schlegel, the study’s senior author. “Although this study doesn’t look directly at fertility, we can infer that as many as half of men taking SSRIs have a reduced ability to conceive. These men should talk with their physician about their treatment options, including non-SSRI depression medications.”
Male circumcision cuts risk of cancer-causing virus
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Circumcision protects men from genital herpes and a virus that causes genital warts and cancer but it does not appear to guard against syphilis, U.S. and Ugandan researchers said on Wednesday.
The report in the New England Journal of Medicine adds to the debate over whether men and newborn boys should be circumcised to protect their health and perhaps the health of their future sexual partners.
The findings from two trials in Uganda build on related research showing that circumcision cuts a man’s risk of HIV infection through heterosexual intercourse by more than 50 percent, said Anthony Fauci of the National Institutes of Health in the United States, which funded the study.
