Sunday, September 9, 2007
Did These Subjects Survive?
Its a lazy Sunday. Just got up after a long long snooze. Thought would put up some cerebral photographs. These were forwarded to me with a caption saying: Their Last Photos.
Saturday, September 8, 2007
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Friday, September 7, 2007
God
Hi Friends,
Going away from Medicine to faith today, the following series of pictures was one of the best e-mail forwards I have received in my life!
God Bless
Thursday, September 6, 2007
The Viagra Alarm
Viagra, the 'wonder-drug' promoted for its ability to relieve impotence in men, may have some unwanted side-effects. Research presented recently in Cheltenham, UK, at the annual meeting of the British Fertility Society, suggests that men who are taking Viagra when trying to start a family may actually be decreasing their ability to father a child. However, Viagra manufacturers Pfizer deny that the drug causes fertility problems.
Viagra was designed to enable an increase of blood flow to the penis to overcome impotence problems. However, since its release it has increasingly been used 'recreationally', and is also used by fertility clinics in order to aid patients' semen production. Viagra is what is known as a 'phosphodiesterase inhibitor', a type of chemical known to affect sperm function, so the study looked at what effect the drug has on sperm. The researchers discovered that using Viagra speeds up chemical changes within sperm, rendering them infertile by the time they reach an egg. This chemical change, known as the acrosome reaction, normally only occurs when a sperm reaches an egg, and is when sperm release enzymes that break down the outer layer of the egg allowing the sperm head to penetrate it more easily. However, if the acrosome reaction occurs too early, the sperm become ineffective and unable to enter the egg, as they have no digestive enzymes left.
Scientists from the School of Medicine, Obstetrics and Gynaecology at Queen's University, Belfast, took 45 semen samples and split them into two groups. Half of the samples were treated with Viagra, while the other half was used as control. The research team found that while Viagra increased sperm motility, up to 79 per cent more sperm in the Viagra-treated samples had clearly undergone premature acrosome reactions. These findings lead the researchers to say they had 'significant concerns for Viagra use in assisted reproduction'. They added that the findings echo previous studies in mice that showed that the presence of Viagra meant that fewer eggs would be fertilised and fewer resulting embryos developed normally.
Dr Sheena Lewis, a member of the team, said that their 'message is that caution should be taken when using recreational drugs if you are hoping to start a family'. But a representative of the European Society for Sexual Medicine, Dr John Dean, said it was important that the study wasn't reported in an alarmist fashion, adding that sperm is highly sensitive in laboratory conditions. 'Childless couples - and the general population - should be aware that in the five years that Viagra has been around no overall detrimental effect on fertility has been observed', he said.
However, Pfizer says that there has been no evidence of Viagra affecting fertility following its use by 23 million men over six years. 'It's one study and it was in a test tube basically, not in real people', said spokesman David Watts.
Viagra was designed to enable an increase of blood flow to the penis to overcome impotence problems. However, since its release it has increasingly been used 'recreationally', and is also used by fertility clinics in order to aid patients' semen production. Viagra is what is known as a 'phosphodiesterase inhibitor', a type of chemical known to affect sperm function, so the study looked at what effect the drug has on sperm. The researchers discovered that using Viagra speeds up chemical changes within sperm, rendering them infertile by the time they reach an egg. This chemical change, known as the acrosome reaction, normally only occurs when a sperm reaches an egg, and is when sperm release enzymes that break down the outer layer of the egg allowing the sperm head to penetrate it more easily. However, if the acrosome reaction occurs too early, the sperm become ineffective and unable to enter the egg, as they have no digestive enzymes left.
Scientists from the School of Medicine, Obstetrics and Gynaecology at Queen's University, Belfast, took 45 semen samples and split them into two groups. Half of the samples were treated with Viagra, while the other half was used as control. The research team found that while Viagra increased sperm motility, up to 79 per cent more sperm in the Viagra-treated samples had clearly undergone premature acrosome reactions. These findings lead the researchers to say they had 'significant concerns for Viagra use in assisted reproduction'. They added that the findings echo previous studies in mice that showed that the presence of Viagra meant that fewer eggs would be fertilised and fewer resulting embryos developed normally.
Dr Sheena Lewis, a member of the team, said that their 'message is that caution should be taken when using recreational drugs if you are hoping to start a family'. But a representative of the European Society for Sexual Medicine, Dr John Dean, said it was important that the study wasn't reported in an alarmist fashion, adding that sperm is highly sensitive in laboratory conditions. 'Childless couples - and the general population - should be aware that in the five years that Viagra has been around no overall detrimental effect on fertility has been observed', he said.
However, Pfizer says that there has been no evidence of Viagra affecting fertility following its use by 23 million men over six years. 'It's one study and it was in a test tube basically, not in real people', said spokesman David Watts.
Wednesday, September 5, 2007
Can a woman's prepregnancy weight influence their son's sperm count?
Men whose mothers were obese before becoming pregnant may be prone to poor semen quality, a pilot study suggests. The research, by a Danish team, used information on 347 men born in 1984-7 and monitored as part of a national pregnancy cohort. All men had semen and blood samples analyzed to indicate their reproductive status. The study found a significant inverse correlation between men's inhibin B levels and their mother's pre-pregnancy body mass index (BMI). Several other markers of fecundity, including sperm concentration, semen volume, percent motile sperm, testosterone, and follicle-stimulating hormone levels, showed trends toward being impaired among sons of overweight mothers. None of the associations was statistically significant, however.
Craha Ramlau-Hansen, from University of Aarhus in Denmark, and co-authors remark that fat is a hormonally active tissue and that being overweight is associated with reduced fecundity in both women and men. In addition, men's BMI is associated with semen quality and reproductive hormonal status. "Our results suggest that there may be an effect of high maternal BMI on the sons' semen quality," the authors conclude. "We encourage others who have the necessary data to follow-up on this important hypothesis."
Guess this is another strong reason to go the Anjali Mukherjee diet.
Craha Ramlau-Hansen, from University of Aarhus in Denmark, and co-authors remark that fat is a hormonally active tissue and that being overweight is associated with reduced fecundity in both women and men. In addition, men's BMI is associated with semen quality and reproductive hormonal status. "Our results suggest that there may be an effect of high maternal BMI on the sons' semen quality," the authors conclude. "We encourage others who have the necessary data to follow-up on this important hypothesis."
Guess this is another strong reason to go the Anjali Mukherjee diet.
Tuesday, September 4, 2007
Evaluating assisted reproduction outcomes 10 years after the introduction of an oocyte donation program
The use of donated oocytes for IVF is highly successful and offers nearly 100 percent pregnancy rates after five treatment cycles, a Spanish team reports. José Remohà (Instituto Valenciano de Infertilidad, Valencia, Spain) and colleagues reviewed reproductive outcomes in a total of 10537 oocyte donation cycles performed at a university-affiliated infertility clinic between 1995 and 2005. Overall rates of pregnancy, implantation, clinical pregnancy, and miscarriage per embryo transfer were 54.9 percent, 27.0 percent, 50.3 percent, and 19.0 percent, respectively. Rates of twin and higher-multiple pregnancies were 39.0 percent and 6.0 percent, respectively. Over the study period, the mean number of embryos transferred fell from 3.6 to 1.9, and both implantation and ongoing pregnancy rates improved significantly.
"Pregnancy rates did not differ among different indications for oocyte donation, age groups, or origin of sperm used for oocyte insemination," the authors comment. Cumulative pregnancy rates were 87.0 percent after three cycles and 96.8 percent after five cycles, indicating that success does not diminish with consecutive attempts. The authors say that oocyte donation has the advantage of being effective independent of the cause of female infertility and severity of male infertility, and conclude that their IVF using oocyte donation is "highly successful."
"Pregnancy rates did not differ among different indications for oocyte donation, age groups, or origin of sperm used for oocyte insemination," the authors comment. Cumulative pregnancy rates were 87.0 percent after three cycles and 96.8 percent after five cycles, indicating that success does not diminish with consecutive attempts. The authors say that oocyte donation has the advantage of being effective independent of the cause of female infertility and severity of male infertility, and conclude that their IVF using oocyte donation is "highly successful."
Monday, September 3, 2007
Premature Ovarian Failure (POF)
A new study has identified risk factors associated with the development of premature ovarian failure (POF) and early menopause. Researchers from centers in Chungju, Seoul and Ilsan, in the Republic of Korea, set out to identify premenopausal risk factors associated with idiopathic POF and early menopause in Korean women, and to find out if the risk factors for POF are distinct from those for early menopause.For the study, menopause was defined as a period of amenorrhea of more than 12 consecutive months. POF was defined as the cessation of menstruation before the age of 40 years, and early menopause was defined as the occurrence of menopause at age 40-44 years. The study population, recruited from local districts as part of a larger study investigating cancer, consisted of 84 women with idiopathic POF, 261 women with idiopathic EM (women with surgical or medical menopause were excluded) and a control group of 1,318 women with ‘normal’ menopause, at age 45-60. The women provided information on their premenopausal lifestyle and reproductive factors.
The main findings of the study, reported in a new paper in the journal Maturitas, include:
Cigarette smoking was significantly associated with idiopathic POF, but not early menopause: the odds ratio of developing idiopathic POF was 1.82 for women who had ever smoked, compared with those who had never smoked. Environmental smoking (defined as a woman living in the same house for at least 1 year prior to menopause with a family member who smoked at least 20 packs of cigarettes in a lifetime) was also significantly associated with idiopathic POF, but not early menopause.
Being 13 years-old or younger at menarche significantly increased the risk of idiopathic POF and idiopathic early menopause.
Having a regular menstruation cycle (defined as occurring every 21-35 days) significantly reduced the risk of idiopathic POF and idiopathic early menopause (odds ratio 0.55, 95 percent confidence interval 0.32-0.95).
Using oral contraceptives significantly reduced the risk of idiopathic early menopause, but not idiopathic POF.
Among parous women, breast-feeding for 24 months or more significantly reduced the risk of idiopathic POF, but not early menopause.
Other environmental, physical and reproductive factors investigated – including alcohol consumption, physical activity per week, sedentary time per day, exposure to agricultural chemicals, parity, and spontaneous abortion in the first pregnancy – did not show any significant relationship with idiopathic POF or early menopause.
The researchers discuss their findings in detail, including the biological mechanisms likely to account for some of the associations such as with cigarette smoking. They conclude that they were able to identify some risk factors that were specific to either POF or early menopause, but that many of the risk factors related to ovulation, such as later menarche, irregular menstruation, and longer duration of breast feeding, were common to both POF and early menopause.
The main findings of the study, reported in a new paper in the journal Maturitas, include:
Cigarette smoking was significantly associated with idiopathic POF, but not early menopause: the odds ratio of developing idiopathic POF was 1.82 for women who had ever smoked, compared with those who had never smoked. Environmental smoking (defined as a woman living in the same house for at least 1 year prior to menopause with a family member who smoked at least 20 packs of cigarettes in a lifetime) was also significantly associated with idiopathic POF, but not early menopause.
Being 13 years-old or younger at menarche significantly increased the risk of idiopathic POF and idiopathic early menopause.
Having a regular menstruation cycle (defined as occurring every 21-35 days) significantly reduced the risk of idiopathic POF and idiopathic early menopause (odds ratio 0.55, 95 percent confidence interval 0.32-0.95).
Using oral contraceptives significantly reduced the risk of idiopathic early menopause, but not idiopathic POF.
Among parous women, breast-feeding for 24 months or more significantly reduced the risk of idiopathic POF, but not early menopause.
Other environmental, physical and reproductive factors investigated – including alcohol consumption, physical activity per week, sedentary time per day, exposure to agricultural chemicals, parity, and spontaneous abortion in the first pregnancy – did not show any significant relationship with idiopathic POF or early menopause.
The researchers discuss their findings in detail, including the biological mechanisms likely to account for some of the associations such as with cigarette smoking. They conclude that they were able to identify some risk factors that were specific to either POF or early menopause, but that many of the risk factors related to ovulation, such as later menarche, irregular menstruation, and longer duration of breast feeding, were common to both POF and early menopause.
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