ISLAMABAD – Penn State College of Medicine researchers have found that losing weight does not lead to improved fertility in women, but does improve sexual function.
“Obesity in women has been linked to lack of ovulation and thus infertility,” said Richard Legro, MD, professor of obstetrics and gynaecology.
“Obesity, especially cantered in the abdomen, among infertile women seeking pregnancy is also associated with poor response to ovulation induction and with decreased pregnancy rates,” he noted. Obese women are often told to lose weight prior to conception, so researchers looked at changes in reproductive function after gastric bypass surgery.
One way to learn more about the effects of obesity on reproduction is to study women after bariatric surgery, since a large amount of weight is lost in a relatively short period of time.
Each person can be studied while obese and after surgery to detect changes.
Researchers followed 29 morbidly obese women - women whose body fat accumulated to the extent that it may have an adverse effect on health - of reproductive age for up to two years after Roux en Y gastric bariatric bypass surgery. Roux en Y is a procedure that creates a small pouch in the stomach that is directly connected to the midsection of the small intestine, bypassing the rest of the stomach and the upper portion of the small intestine.
Ovulation frequency and quality was determined by collecting daily urine specimens over the course of a menstrual cycle and measuring ovarian hormones.
The researchers were surprised to find that ovulation rates remained high (more than 90 percent at all time points before surgery and at one, three, six, 12, and 24 months after surgery). The quality of the ovulation also remained unchanged, and there was little effect on the ovarian cycle.
The exception is a notable shortening of eight to nine days of the follicular phase. The follicular phase is the first half of the menstrual cycle from the end of the previous menstrual flow until the release of the egg (ovulation). Three months after surgery, the phase is six and a half days shorter, and then up to nine days shorter by 24 months post-surgery.
Obesity is associated with longer menstrual cycles, specifically because of an increase in the follicular phase.
The reason the phase shortens with weight loss is not yet known.
Sexual function at one year as detected by the Female Sexual Function Index, a self-reporting index of sexual health collected through questionnaires, is most noticeable. This improvement is independent of changes in hormone levels and body composition. Sexual desire and arousal increase the most.
Researchers did not track sexual activity or desire to conceive. However, increased sexual desire may have led to increased frequency of sexual activity.
“The effects of weight loss on reproductive function are more modest than we hypothesised. In terms of ovulation, there doesn’t appear to be a window after surgery where fertility is improved,” Legro said.
“The door appears to be open at all times. Other factors may be involved with infertility in obese women, such as diminished sexual desire and thus less intercourse. This study, to our knowledge, is the largest, most comprehensive and longest study of female reproductive function before and after Roux en Y gastric bariatric surgery,” he added.
Researchers reported their findings in the Journal of Clinical Endocrinology and Metabolism.
A dose of young blood may avert Alzheimer’s: Study
Filtering younger blood into an older body could combat the problem of deteriorating memory by rejuvenating old tissues and keeping nerve cells in good working order, researchers say.
Changes in the composition of our blood as we age may cause the deterioration of memory and other brain functions by damaging connections in the brain.
This means that people in their 40s or 50s could in future be given blood donated by someone in their early twenties to prevent their brain from deteriorating and stave off memory-related diseases like Alzheimer’s.
Researchers from Stanford University found that old mice given transfusions of younger blood performed better in a memory task than those left to age naturally.
They also began to re-grow connections in their brains which had previously begun to disappear as part of the aging process and which affect memory.
Dr Saul Villeda, who led the research, said he now plans to test the therapy on a mouse model of Alzheimer’s disease, in which brain connections break down and cause loss of memory and learning ability.
“I think any sort of disease that has that component, there is a chance this might help,” the Telegraph quoted Villeda as saying.
“What I am thinking is if we can address it earlier, when our body still has the control to prevent this from happening, then we might not have to cure Alzheimer’s, we might just be able to stop it,” Villeda said.
According to Villeda, older people’s blood may damage the brain and other parts of the body like the muscles and vital organs because it contains a greater number of inflammatory proteins in its plasma.
He gave a group of 18-month old mice, which were nearing the end of their lifespans, eight transfusions of younger mice’s plasma over the course of a month, adding up to five per cent of their total blood supply.
They were then put in a water maze where they had to learn the route to a hidden platform on which they could stand. Untreated mice usually made two or three wrong turns but the treated group were able to find the right path most of the time.
“They were 18 months old but they were acting much younger, like a four to six-month-old,” Dr Villeda said.
He also found that mice given a younger blood supply began to sprout new synapses in their brains, which carry messages between nerve cells, giving them 20 percent more than the untreated mice on average.
The findings of the study were presented at the Society for Neuroscience conference.