Saturday, March 31, 2007

Fathers Age Responsible for up to 50% of risk of Down Syndrome if the Mother is also over 40

July 1, 2003 -- Older fathers may contribute just as much as older mothers to the dramatic increase in Down syndrome risk faced by babies born to older couples. A new study found that older fathers were responsible for up to 50% of the rise in Down syndrome risk when the mother was also over 40.

Researchers say the number of births to parents over age 35 has more than doubled in the last 20 years and this has raised questions about the role of paternal age in the risk of genetic abnormalities and birth defects.

The study showed that the percentage of births to women over 35 grew from 8% of all births in 1983 to 17% in 1997, and the greatest change during this period was the number of births to mothers and fathers over 40 years old, which rose by 178% and 73%, respectively.

Researchers found that the rate of Down syndrome among parents over 40 was 60 per 10,000 births, which is six times higher than the rate found among couples under 35 years old. Older fathers over 40 had twice the rate of Down syndrome births compared with men 24 years old and younger when they had children with women over 35.

"Paternal age has an effect on Down syndrome but only in mothers 35 years old and older," write researcher Harry Fisch, MD, of the department of urology at Columbia-Presbyterian Medical Center in New York City, and colleagues. "In younger women, in whom age was not a risk factor for Down syndrome, there was no paternal effect."

Among older mothers over 40, researchers found that an increase of 50% in Down
syndrome risk was attributable to the advanced age of the father.

"Young couples preparing for family planning must be aware that advanced parental age may not only result in increasing difficulties with fertility for the parents but that children born to older parents may be at higher risk for genetic abnormalities,"


Thursday, March 29, 2007

It's A Time Bomb!

It's a Time Bomb!

Article by Tamar Lewin 2001

Ideas & Trends: Reproductive Gerontology; Ask Not for Whom the Clock Ticks!

MEN, take note: you, too, have a biological

True, it does not tick toward the absolute deadline that ends women's childbearing years. As notables like Tony Randall, Yasir Arafat, George Plimpton, Anthony Quinn, Clint Eastwood, Strom Thurmond and so, so many more have demonstrated, men can father babies no matter how old they get.
But there is a growing body of evidence that the fruit of aging loins is burdened with increased risk of a wide variety of gene-influenced illnesses. A study released last week raised the intriguing -- if skeptically viewed -- possibility that some cases of schizophrenia fall into that category.


Reduced Fertility and Advancing Paternal Age

Advanced paternal age: How old is too old?
Isabelle Bray, David Gunnell and George Davey Smith
Department of Social Medicine, University of Bristol, UK

Correspondence to:
Dr I Bray
Department of Social Medicine, University of Bristol, Canynge Hall, Whiteladies Road, Bristol BS8 2PR, UK;

Average paternal age in the UK is increasing. The public health implications of this trend have not been widely anticipated or debated. This commentary aims to contribute to such a debate. Accumulated chromosomal aberrations and mutations occurring during the maturation of male germ cells are thought to be responsible for the increased risk of certain conditions with older fathers. Growing evidence shows that the offspring of older fathers have reduced fertility and an increased risk of birth defects, some cancers, and schizophrenia. Adverse health outcomes should be weighed up against advantages for children born to older parents, mindful that these societal advantages are likely to change over time.

Labels: , ,

Sunday, March 25, 2007

Miscarriages/Spontaneous Abortions and Paternal Age

Advancing paternal age has been found to be a potent factor in some miscarriages.

Various recent studies have found this:

The frequency of chromosomal anomalies in spermatozoa appears to increase with male age. Because these anomalies play a role in the etiology of spontaneous abortion, an influence of paternal age on risk of spontaneous abortion is plausible but not established. The aim was to characterize this influence in a prospective study among 5,121 California women, who as members of a prepaid health plan were interviewed in 1990 or 1991 when they were less than 13 weeks' pregnant and who were followed until the end of pregnancy. The risk of spontaneous abortion between weeks 6 and 20 of pregnancy was studied using a Cox model adjusted for maternal age. The adjusted hazard ratio of spontaneous abortion associated with paternal age of 35 years or more, compared with less than 35 years, was 1.27 (95% confidence interval: 1.00, 1.61), with no modification by maternal age. Among women aged less than 30 years, the hazard ratio of spontaneous abortion associated with paternal age of 35 years or more was 1.56 for first trimester spontaneous abortion and 0.87 for early second trimester spontaneous abortion (test of interaction, p = 0.25). In conclusion, the risk of spontaneous abortion increased with increasing paternal age, with a suggestion that the association is stronger for first trimester losses.

another recent study

RESULTS: The adjusted odds ratio for spontaneous abortion was 0.59 (95% confidence interval 0.45–0.76, P< .0001) for pregnancies conceived from fathers aged younger than 25 years compared with those from fathers aged 25–29 years. For fathers age 40 years or older the odds ratio for spontaneous abortion was 1.6 (95% confidence interval 1.2–2.0, P=.0003) when compared with the same reference group.

CONCLUSION: Increasing paternal age is significantly associated with spontaneous abortion, independent of maternal age and multiple other factors.


Labels: , ,

Saturday, March 24, 2007

The Paternal Age Effect

The relationship between advanced paternal age and genetic disorders in offspring was noticed by Wilhem Weinberg, a physican who delivered thousands of babies.
Weinberg was born in Stuttgart and studied medicine at Tübingen and Munich, receiving an M.D. in 1886.

He observed that the last born, or late born children were sometimes abnormal.

There is much literature on the paternal age effect.

Labels: , ,

What is advanced paternal age 33 35 40?

There is disagreement about the definition, advanced maternal age is 35, from the evidence I've collected 33-35 is when spontaneous mutations in sperm begin to increase rapidly. These mutations may affect the next generation or future generations.

New mutations on the X chromosome are usually not evident in the children. They are transmitted to daughters who are at risk for having sons with X-linked diseases. This is an indirect paternal age effect; it is the effect of the age of the maternal grandfather.

Examples of autosomal dominant conditions associated with advanced paternal age include achondroplasia, neurofibromatosis, Marfan syndrome, Treacher Collins syndrome, Waardenburg syndrome, thanatophoric dysplasia, osteogenesis imperfecta, and Apert syndrome.

Examples of X-linked conditions associated with increased maternal grandfather's age include fragile X, hemophilia A (factor VIII deficiency), hemophilia B (factor IX deficiency), Duchenne muscular dystrophy, incontinentia pigmenti, Hunter syndrome, Bruton-type agammaglobulinemia, and retinitis pigmentosa.

Labels: , ,

Tuesday, March 20, 2007

Dr. Narendra P. Singh, Unversity of Washington

"One of the best markers we have of the male biological clock is an increase in DNA-damaged sperm. At age 25, only 5 percent of a man's sperm has DNA damage; by age 35, that percentage has grown to 20 percent. That's a fourfold increase in just ten years. As the percentage of damaged sperm increases, the odds of fertilization decrease." — Narendra Singh, associate professor in the Department of Bioengineering at the University of Washington, Seattle

In a study examing the sperm of 66 men aged 22-80. Dr.Narendra P Singh, Dr. Charles Mueller, and Dr. Richard Berger found....

The researchers found that men over age 35 had sperm with lower motility and more highly damaged DNA in the form of DNA double-strand breaks. The older group also had fewer apoptotic cells -- an important discovery, Singh said.

"A really key factor that differentiates sperm from other cells in the body is that they do not repair their DNA damage," he said. "Most other cells do."

As a result, the only way to avoid passing sperm DNA damage to a child is for the damaged cells to undergo apoptosis, a process that the study indicates declines with age.

"So in older men, the sperm are accumulating more damage, and those severely damaged sperm are not being eliminated," Singh said. "That means some of that damage could be transmitted to the baby." More research is needed to determine just what the risks are......

Labels: , ,

Dr. Nancy Snyderman and The Male Biological Clock on the Today Show
caught up with Dr. Nancy after her segment on the male biological clock this morning. I asked her what the one take-away point should be from the segment, and she said quite simply: "There is one." That is, there IS a male biological clock, and it's something that everyone should take into account when family planning and deciding to have children. The female biological clock often receives the attention because it's a clear and simple fact -- women cannot have children after a certain age. However, men can still reproduce at any age, and that's the reason that the male risk factors often drop off the radar screen.

Some of the statistics are quite alarming, however. Of the nearly 6 million fertility problems in the US each year, roughly 40% of them are attributed to the man. Of all the babies born with Down Syndrome to women over the age of 35, HALF of them are actually sperm-related. (Source for both statistics: Dr. Harry Fisch, director of the Male Reproductive Center at New York-Presbyterian Hospital/Columbia University Medical Center.) There are other studies out there that are still being discussed, with possible links between the male biological clock and diseases such as autism and schizophrenia.

And both men and women should be aware of the male biological risk factors, rather than solely focusing on the woman's age. She was emphatic about this story, and wants as many people to listen up as possible. WATCH VIDEO.

Labels: , , ,

Dr. Emily Senay on the Early Show

Evidence Of Male Biological Clock Mounts
Senay: More Studies Show Men's Ability To Father Healthy Kids Diminishes With Age
NEW YORK, March 5, 2007

Senay observed that the notion of a male biological clock isn't as new as many people think.

A leading researcher in the field says basic knowledge of age-related changes in men's sperm goes back to the 1950s. She says it's intriguing that society chooses to ignore this information.

Senay herself told Smith, "I think there's a resistance, if you will, or even a measure of denial."

Labels: , , , ,

The NY Times science section On the male biological clock

Older fathers appear to raise risks of genetic disorders

By Roni Rabin Published: February 28, 2007

When it comes to fertility and the prospect of having normal babies, it has always been assumed that men have no biological clock — that unlike women, they can have it all, at any age.

But mounting evidence is raising questions about that assumption, suggesting that as men get older, they face an increased risk of fathering children with abnormalities. Several recent studies are starting to persuade many doctors that men should not be too cavalier about postponing marriage and children.

Until now, the problems known to occur more often with advanced paternal age were so rare they received scant public attention. The newer studies were alarming because they found higher rates of more common conditions — including autism and schizophrenia — in offspring born to men in their middle and late 40s. A number of studies also suggest that male fertility may diminish with age.

Labels: , , ,

A article about Male Infertility and Age and Stamina to be a Good Father

Guys: The biological bell tolls on thee, too
By Mark de la Vina, MEDIANEWS STAFF
Article Last Updated: 02/27/2007 07:41:48 AM PST

Men having children past 40 is generally not a good idea, says Chris Mason, 46, of Danville. The father of three daughters by the time he was in his 30s, Mason says that he wouldn't consider having a fourth child, even if something were to happen to his wife.

Labels: , ,

Ageless Fatherhood? Maybe Not--- a very good article


c. 2007 HealthDay News
Distributed by The New York Times Syndicate
This is the first of four recent article or TV spots on this vitally important topic.
Here are some extensive excerpts:

.............."Several studies have found that older fathers risk having children with medical problems, including Down syndrome. Fisch and his colleagues evaluated more than 3,400 cases of Down syndrome, finding that if the woman and the man were both over age 35 at the time of conception, the father's age played a role in prevalence of the disorder. This effect was most pronounced when the woman was over 40, the researchers found. And, in those cases, the incidence of Down syndrome was about 50 percent attributable to the sperm, the researchers said. The study was published in 2003 in The Journal of Urology.

In another study, Dr. Avraham Reichenberg, of Mount Sinai School of Medicine in New York City, found that advanced age for fathers is associated with an increased risk of autism. His team gathered data on the age of fathers of more than 318,000 people born in Israel during the 1980s. The researchers found that the chances of having a child with autism or a related disorder were about six times greater if the father was 40 or older, compared to men 29 or younger. The findings were published in the September 2006 issue of The Archives of General Psychiatry.

Still another study found that the risk of schizophrenia in children was tied to older age of the father. In the study, which included about 90,000 people, the researchers discovered that children whose fathers were 50 or older when they were born were nearly three times more likely to have the disorder than those born to younger fathers. That study was published in 2001 in The Archives of General Psychiatry.

Another study, published in 2002 in Human Reproduction, found a higher risk of miscarriage in mothers 35 and older and fathers 40 and older.

And, in 2004, The Journal of the American Medical Association reported that 20 different disorders in children, ranging from schizophrenia to skeletal disorders, have been linked to the advanced age of the father......................

Orignally published February 27, 2007

Labels: , , ,

Sunday, March 11, 2007

Sperm Banking In the Press In Mumbai and Delhi

Healthy young men in two cities in India are using cryobanking for future fathering of babies.

NEW DELHI: Call it innovative insurance. More and more young men in Delhi who are busy chasing fast-track careers, but are not yet ready to start a family, are choosing to freeze their sperms — to be used when they are ready.

More than 50% of the long-term frozen samples in Delhi's sole commercial sperm banking organisation, Cryogenie, are of healthy young men who are not ready for procreation and do not want to rely on donor sperms either.

Says Dr Iqbal Mehdi, head of cryobanking services at Cryogenie, "The long-term banking facility was initially started with malignancy patients in mind. People who undergo chemo or radiotherapy often suffer from low sperm counts so they store semen before the treatment starts. It was much later that we realised that freezing of sperms gave healthy individuals the option of starting a family when they want to, no matter what their age."

Add to this the changing attitude among women. With an increasing number putting marriage and children on a standby mode the average conceiving age of women is now early-30s, up from mid-20s a couple of years back.

This trend, however, has left women in urban India with an average of just 5-6 ‘good years’ to get pregnant. “Women are unwilling to wait. They would rather use the intrauterine insemination technique that involves injecting sperm in the uterus,” says Anjali Malpani.

Labels: , , , , ,

Friday, March 09, 2007

James F. Crow Professor Emeritus Population Genetics University of Wisconsin

Genetic Mutations Tied To Father in Most Cases

An excellent article from 1994

Published: May 17, 1994

Some excerpts ................................
"WHEN it comes to parceling out blame for birth defects and genetic disorders, women have historically shouldered most of the burden, particularly older mothers who supposedly risked their offspring's well-being by letting their eggs sit around growing progressively more stale and chromosomally unstable.

By contrast, men have been seen as eternally fertile, able to father healthy children well into their dotage.

But growing evidence suggests that men, rather than women, may be the source of most new genetic mutations in the population, and thus may be responsible for the majority of congenital diseases that seem to come from nowhere. In addition, the older the man gets, the more likely his sperm is to carry genetic mutations.

The new view is based largely on studies of individual cells, and scientists emphasized that they have much to learn about the source of genetic mutations. Nor do they have any idea how often a minor variation in the genetic blueprint for a human being translates into a birth defect. The overwhelming majority of genetic alterations that appear in the course of generating sex cells are likely to be harmless. Nevertheless, some researchers said it was time to take a closer look at the inherent fallibility of sperm cells.

"This is a subject that has not received as much attention as it should," said Dr. James F. Crow, a geneticist at the University of Wisconsin in Madison.

As long as half a century ago, J. B. S. Haldane, the great Scottish geneticist, proposed that new cases of hemophilia not associated with a family history of the disease were much more likely to be the result of a genetic glitch originating with the male's sperm rather than with the female's egg. Scientists realized that while a woman's eggs are fully formed during fetal development and undergo no further cell division after birth, the progenitor sex cells that give rise to a man's sperm continue to divide throughout his life. And the greater the number of cell divisions, the greater the odds that minor errors called point mutations can occur while the chromosomes are being copied.

More recently, scientists have shown that genes on the Y chromosome -- the sole province of the male -- do indeed mutate at a faster rate than genes on the X chromosome, which is essentially though not exclusively a female chromosome. Using these and other new findings, scientists estimate that the overall genetic mutation rate in sperm cells is six times greater than it is in eggs. The Aging Factor

That discrepancy only widens with age. The older a man is, the more times his progenitor sperm cells have divided, and so the higher the number of possible point mutations that may have piled up in the chromosomes.

At 13, when a boy typically begins making sperm, his sex cells have divided about 36 times, and they divide about 23 times a year thereafter. By age 20, the cells have replicated about 200 times; by 30, about 430 times; and by 45, about 770 times.

Statistical evidence supports the premise that an older father is likelier to sire a child with a birth defect than is a younger man, Dr. Crow said. On average, fathers of children who have a new dominant genetic disorder -- a disease caused by a single genetic defect not known to run in the family -- are six years older than fathers of children without an illness. For example, older fathers have an elevated risk of giving birth to children with achondroplastic dwarfism, Marfan syndrome and myositis ossificans, a disease of bony tissue."............................

"I think we could eliminate quite a bit of human mutation if males either reproduced at a young age, or stored their youthful sperm on nitrogen for use later in life," he said.

James F. Crow's paper the High Rate of Spontaneous Mutation:Is it a health risk? Is very important work to read if you can.

Labels: , ,

Photarium blog directory Blog Directory - photarium Outpost