2015-09-01T15:36:07+00:00In recent years, evidence has been building that injectable contraceptive depot medroxyprogesterone acetate (Depo-Provera or DMPA) is associated with an increased risk of HIV infection. Now a study published in the September 1st issue of mBio, an online open-access journal of the American Society for Microbiology, provides a biological explanation for the phenomenon. The findings will help women make more informed choices about birth control. “Before this study, there were all these controversial reports, some showing that DMPA increases the risk of HIV infection and others showing it doesn’t, and there was no biologic explanation for the differences between studies,” said lead author Raina Fichorova, PhD, MD, director of the Division of Genital Tract Biology at Brigham and Women’s Hospital and associate professor of obstetrics and gynecology and reproductive biology at Harvard Medical School, Boston. “This new study offers an explanation for the inconsistent studies, and it lies in the microbial communities of the reproductive tract.” The researchers analyzed cervical swabs and data from 823 women, between the ages of 18 and 35, who were HIV negative and enrolled in family planning clinics in Uganda and Zimbabwe. Roughly 200 women in this cohort became HIV infected. Women were divided into three groups, those who used DMPA, those who used estrogen-progesterone oral contraceptives, and those who used no hormonal contraceptives. Within each of these groups, the investigators compared results for women with a healthy vaginal environment (dominated by Lactobacillus-morphotypes and free of bacterial vaginosis) to women who had a disturbed vaginal microbioata or an infection from bacteria, fungi or parasites.
2015-06-17T16:05:59+00:00Teenagers vary substantially in their ability to control impulses and regulate their behavior. Adolescents who have difficulty with impulse control may be more prone to risky sexual behavior, with serious consequences such as sexually transmitted diseases and unintended pregnancies. A new study has found that individual differences in working memory can predict both early sexual activity and unprotected sexual involvement during adolescence. Working memory - the system in the brain that allows individuals to draw on and use information to plan and make decisions - develops through childhood and adolescence. The new study found that adolescents with weaker working memory have more difficulty controlling their impulsive urges and considering the consequences of their behaviors. The study was carried out by researchers at the University of Oregon, the University of Pennsylvania, and the Children’s Hospital of Philadelphia. It appears in the journal Child Development. Prior research in this field has linked impulsivity and lack of self-control to risky behaviors during adolescence. This study builds on earlier findings, focusing instead on cognitive abilities, such as the ability to concentrate on tasks and filter out distractions, which rely on working memory.
2015-06-17T15:57:39+00:00Chances are good that women with a low heart rate variability also suffer from sexual dysfunction. That’s the finding from a study led by Amelia Stanton of The University of Texas at Austin in the US published in Springer’s journal Applied Psychophysiology and Biofeedback. Heart rate variability refers to differences in the length of time between consecutive heartbeats. It is one of the most sensitive and objective measures of the interplay between the sympathetic nervous system (which activates the so-called fight or flight response) and the parasympathetic nervous system (which regulates the body’s unconscious actions such as heart beat and breathing). Together, these form the autonomic nervous system. If this is in balance and functioning properly, a person will be able to adapt to physiological or environmental changes and stresses when needed. Heart rate variability, in particular, plays a role in female sexual arousal function. It is a marker of a healthy heart and the body’s ability to modulate blood pressure appropriately within various contexts. This is important because sexual arousal is largely a matter of the selective manipulation of blood pressure in the genitals. Heart rate variability also relates to the processing of emotional cues. In this context, low resting heart rate variability may reflect poor emotional health and vice versa.
2015-06-10T21:00:40+00:00Forget those ageist stereotypes that senior citizens have little interest in sex and are befuddled by technology. Many older adults are going online to dish about the joys of sex and swap advice about keeping their mojos working well into their twilight years, a new study found. “Many older people preserve both a high interest in sex and a high involvement in sexual activities,” said researcher Liza Berdychevsky, a professor of recreation, sport and tourism at the University of Illinois who researches sexual behavior and well-being. “The popularity of sex-related discussions in seniors’ online communities suggests that, in a reality of limited alternatives for open and direct sex-related communication, seniors are finding channels to satisfy their needs for information and support.” Berdychevsky and co-author Galit Nimrod, a faculty member at Ben-Gurion University of the Negev, Israel, conducted an online ethnographic study - or netnography - in which they examined discussions of sexual topics in 14 online communities geared toward adults age 50 and older. Seven of the websites were based in the U.S., four in the U.K., two in Canada and one in Australia.
2015-05-26T16:47:00+00:00Sperm in the first fraction of ejaculate are more numerous, move more and present better quality DNA than those lagging behind. This is the conclusion of a study led by the Ginemed fertility clinic, which confirms that while the objective of the first fraction is to fertilise the egg, the second phase is so that no sperm from any other male has a chance to fertilise it. A study led by the Ginemed Assisted Human Reproduction Clinic analyses the advantages of using fractions of ejaculate separately in in-vitro fertilisation as a way to improve the sample of the semen. The researchers’ hypothesis was that, comparing the different fractions of semen in an ejaculation, the first would contain sperm with better seminal parameters and could be used as an effective method for selecting sperm prior to fertilisation.
2015-05-20T16:51:16+00:00Men who drink the equivalent caffeine level of two to three cups of coffee a day are less likely to have erectile dysfunction (ED), according to researchers from The University of Texas Health Science Center at Houston (UTHealth). The results of a study published recently in PLOS ONE found that men who consumed between 85 and 170 milligrams of caffeine a day were 42 percent less likely to report ED, while those who drank between 171 and 303 milligrams of caffeine a day were 39 percent less likely to report ED compared to those who drank zero to seven milligrams a day. This trend was also true among overweight, obese and hypertensive men. “Even though we saw a reduction in the prevalence of ED with men who were obese, overweight and hypertensive, that was not true of men with diabetes. Diabetes is one of the strongest risk factors for ED, so this was not surprising,” said David S. Lopez, Dr.P.H., M.P.H., lead author and assistant professor at UTHealth School of Public Health.
2015-05-05T17:44:21+00:00Acceptance of premarital sex is at an all-time high along with an acceptance of homosexuality, find researchers led by Jean M. Twenge from San Diego State University. The researchers - also including Ryne Sherman from Florida Atlantic University and Brooke E. Wells from Hunter College - analyzed data from the General Social Survey, a nationally representative survey of more than 33,000 U.S. adults taken between 1972 and 2012. They found substantial generational shifts in attitudes toward non-marital sex and number of sexual partners. The results were published today in the Archives of Sexual Behavior. “The changes are primarily due to generation - suggesting people develop their sexual attitudes while young, rather than everyone of all ages changing at the same time,” said Twenge, who is also the author of “Generation Me.” “This has caused a large generation gap in both attitudes toward premarital sex and number of sexual partners,” she said.
2015-04-07T18:12:22+00:00Viagra and other related drugs are not a universal ‘cure-all’ for impotence, according to a new study from The University of Manchester and NatCen Social Research. Drugs, clinically known as oral phosphodiesterase type 5 inhibitors (PDE5i), have become the first-line medical treatment option for sufferers of erectile dysfunction (ED) - also known as impotence - since entering the UK market in 1998. An abundance of studies has demonstrated the effectiveness of such drugs. But researchers at The University of Manchester, who have studied the responses of more than 2,600 English men (aged 50-87 years), suggest that restoring ED pharmacologically is not a ‘cure-all’. Lead author of the study, Dr David Lee, found that older sufferers of ED who had used Viagra, or similar drugs such as Cialis and Levitra, still expressed concern or dissatisfaction with their sex lives.
2015-04-06T21:18:59+00:00New mothers in the Philippines spend more time in the bedroom with their partner in the first few weeks after giving birth than they did before they became pregnant. This might be a type of survival strategy to keep the relationships with the fathers of their new babies alive and well, to ensure continued support for their offspring. So says Michelle Escasa-Dorne of the University of Colorado in the US, after studying how women from a society with a low divorce rate such as the Philippines adapt to being both mothers and lovers. The study appears in Springer’s journal Human Nature. A range of studies previously conducted on how women in Western societies experience the first six weeks after giving birth show that they tend to devote more time to their offspring’s well-being than to their partner. This leads to lower relationship satisfaction and less intercourse between partners, and a clear shift from so-called mating efforts to parenting efforts. Escasa-Dorne set out to understand if similar trends are also found among women in a non-Western population with a low divorce rate. She questioned 260 women who were in a relationship and living in the Philippines’ capital of Manila. Of these, 155 women still breastfed. They completed questionnaires about their sexual functioning and menstrual cycles, as well as about how satisfied and committed they were in their current relationships. The women were between 18 and 35 years old, mostly married, well-educated, and had on average two or three children. Breastfeeding women who had already resumed having their periods were more sexually active and committed than others.
2015-04-06T00:08:54+00:00The science on statins and sexual function is inconclusive, but it does appear that taking a statin may sometimes affect a person’s sex life. On the plus side, some men report improved erections when their high cholesterol was treated with statins, said Dr. Steven Nissen, chairman of the department of cardiology at the Cleveland Clinic. It is plausible that lowering cholesterol improves the function of the cells that line blood vessels, which could help erectile function, he said. But a 2008 report from the University of California, San Diego, tells a different story. Researchers looked at statin use and sexual function in 1,000 men and women, half of whom were given a statin and half of whom took a placebo. Over all, men on statins were about twice as likely as those taking placebos to report that their ability to achieve orgasm had become “somewhat worse” or “much worse.” Dr. Beatrice Golomb, a professor at the University of California, San Diego, medical school, who helped conduct that study, says doctors don’t always take patients seriously when they talk about side effects, sexual or otherwise. In other research, Dr. Golomb found that when patients complained about the most commonly recognized side effects of statins, their doctors denied the possibility of a connection more than half the time.
2015-04-01T16:27:29+00:00Published reports of clinical trials provide insufficient information to adequately establish the safety of finasteride for treatment of hair loss in men, according to a new Northwestern Medicine study to be published April 1 in JAMA Dermatology. This study is the first meta-analysis of the quality of safety reporting in clinical trials of finasteride for treatment of male hair loss. Finasteride blocks 5α-reductase in the scalp and male reproductive organs, inhibiting the conversion of the male hormone testosterone to its more potent form, 5α-dihydrotestosterone (5α- DHT). Men who take finasteride experience a 70 percent reduction in the amount of 5α-DHT in their blood. Not one of the 34 published clinical trial reports provided adequate information about the severity, frequency or reversibility of sexual adverse effects. (Adequate quality of adverse event reporting requires using an explicit toxicity scale to grade adverse event severity and reported numbers and/or rates of occurrence for each specific type of adverse event per study arm.)
2015-03-19T20:39:15+00:00There is no doubt that teenage boys and girls are swayed and shaped by music TV. For example, sexually active youth of both genders, after watching music TV, think their peers are sexually active, too. Moreover, when girls and boys perceive males in music videos as being sexually active, it makes boys watch more music TV, and girls watch less. These are some of the surprising findings from a study conducted at the Catholic University of Leuven in Belgium, published in Springer’s journal Sex Roles. The results question the frequently reported blanket influence of the mass media on teenagers’ sexual behavior. Watching music videos is a popular pastime of European and American teenagers. It does however receive its fair share of criticism for having too much sexual content, for objectifying women and for promoting a recreational view of sexual activities involving active men. It has been linked to teenagers’ becoming sexually active earlier in life. Over the course of one year, the researchers gathered information three times from 515 Belgian teenagers between the ages of 12 and 15 years old. They were asked how much music television they watched, how sexually active they were and indeed also how sexually active they thought their peers were. The researchers found that watching sexual music videos only had an effect on the sexual behavior of teenage boys, but not so on girls. The believe such behavior is influenced by the sexual scripts of music videos, which tend to show men taking the more active role in any sexual interaction.
2015-03-09T16:09:19+00:00Working in a physically demanding job, having high blood pressure, and taking multiple medications are among health risks that may undermine a man’s fertility, according to a study by researchers at the National Institutes of Health and Stanford University, Stanford, California. The study is the first to examine the relationships between workplace exertion, health, and semen quality as men are trying to conceive. The results were published online in Fertility and Sterility. “Nearly 15 percent of U.S. couples do not become pregnant in their first year of trying,” said Germaine Buck Louis, Ph.D., the study’s senior author and director of the Division of Intramural Population Health Research at NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development. “Male infertility plays a significant role, and our aim is to explore the influence of environmental factors and health status on semen quality.” Semen quality is a measure of a man’s ability to achieve fertilization and is based on the number, shape, and movement ability of sperm, as well as other factors. The investigators followed more than 500 couples in Texas and Michigan over a yearlong period. The couples were in committed relationships and stopped using contraception. All male participants completed preliminary interviews in which they were asked about their reproductive history, health, lifestyle and occupational activity. Most of the men provided a semen sample for analysis.
2015-02-16T20:17:34+00:00While people in the early years of marriage have sex more frequently, and their sexual activity tapers off over time, a slight rebound occurs for those whose marriages endure longer than half a century, according to new research. The study also found that people who remain in their first marriages have sex more frequently than those who remarry. But frequency aside, marriage order made no difference when it came to actual physical pleasure and emotional satisfaction, said researchers from Louisiana State University, Florida State University and Baylor University. Their study - “Marital Characteristics and the Sexual Relationships of U.S. Older Adults: An Analysis of National Social Life, Health and Aging Project Data” - is published in the journal Archives of Sexual Behavior, the official publication of the International Academy of Sex Research. Researchers analyzed the relationship between marital characteristics and sexual outcomes among 1,656 married adults ages 57-85, using data from the first wave of the National Social Life, Health and Aging Project. They noted that people who survive until their 50th year of marriage - among whom the slight rebound occurred - are relatively few in number.
2015-02-10T02:05:17+00:00Receiving the human papillomavirus vaccine does not increase rates of sexually transmitted infections (STIs) in adolescent females. The vaccine, which can prevent cervical cancer in women, has had a low uptake, partly because of concerns about how it will affect adolescent sexual activity. The findings, based on investigations by researchers at Harvard Medical School and the University of Sothern California, published today in JAMA Internal Medicine, suggest that the vaccine does not promote risky sexual behaviors among those who have received the vaccine. “Since this is one of the few medications ever developed that can actually prevent cancer, it’s good to be able to reassure parents, physicians and policymakers that the vaccine does not promote unsafe sexual practices among girls and young women,” said Anupam Jena, assistant professor of health care policy at HMS, internist at Massachusetts General Hospital and faculty research fellow at the National Bureau of Economic Research. In Australia, which has instituted a national policy of mandatory HPV vaccination, delivered for free through the schools, more than 80 percent of girls ages 14-16 have received at least one of the three recommended doses of the vaccine. In the U.S., the same-dosage rate for girls ages 13-17 is 57.3 percent.