Friday, April 24, 2009

Biological clock ticks for men as well

Biological clock ticks for men as well
By Jenifer Goodwin (Contact) Union-Tribune Staff Writer
8:00 a.m. April 24, 2009
Ever since women began putting off childbearing to go to college and build careers, they've had to face a cold, hard truth. A growing body of research is showing that men have a biological clock, too. - JupiterimagesEver since women began putting off childbearing, they've had to face the harsh truth that there are only so many years they can have babies.
If a woman dares wait until age 35, she's declared “advanced maternal age” and told about the increased risk of having a baby with certain genetic conditions.
As it turns out, a growing body of research is showing that men have a biological clock, too.
The children of older fathers scored lower than the offspring of younger fathers on IQ tests and other cognitive measures at 8 months old, 4 years old and 7 years old, according to results of a study released in March.
Men who becomes fathers in their 40s or older are more than 1.5 times more likely to father children who are autistic, according to a 2006 study.
Other research has shown increased risk of schizophrenia and bipolar disorder in the children of older fathers, and that the risk of miscarriage rises with the father's age.
“Men are in denial,” said Dr. Harry Fisch, an expert on male infertility and author of the 2005 book “The Male Biological Clock.” “Men think as they age, they get better or more distinguished. As men get older, they get older.”
Scientists knew for years before the highly publicized autism and IQ studies that the children of older fathers were at higher risk of certain rare genetic conditions, such as dwarfism, Fisch said.
Yet outside of the science realm, few paid much attention.
Men were operating under the mistaken belief that since they generated new sperm every day, they could have children well into old age with no added risk.
What was missing from the equation was that even new sperm made by an older man is more prone to genetic defects. “As the body ages, there is no reason to think why these sperm cells wouldn't age too,” Fisch said.
So what should men do with the information?
Plenty of older dads father healthy, intelligent children. Still, men should consider the potential consequences of putting off childbearing, Fisch said.
The older both spouses are, the greater the chance they will have fertility problems, he said. “People need to know this information for family planning.”

Jenifer Goodwin: (760) 476-8210; (Contact)

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Wednesday, April 22, 2009

For Whom The Clock Ticks Newsweek

For Whom The Clock Ticks
A growing body of research supports the idea that there are biological disadvantages to late-in-life fatherhood. But will society's view of male fertility ever change?

By Daniel Heimpel | Newsweek Web Exclusive
Apr 22, 2009


In season two of Bravo's wildly popular television series "Millionaire Matchmaker," host Patti Stanger rants against older men who perpetually search for 20-somethings to date. What Stanger knows intuitively and what researchers are illustrating empirically, is that men 50 and older, no matter their financial stability, aren't always the greatest catch.

Even if they can theoretically father children till the day they die, a growing compendium of knowledge points to a male "biological clock" largely driven by the replication of sperm with damaged DNA. According to a number of recent studies, offspring of older men have increased chances of a wide range of problems from autism to psychiatric disorders such as schizophrenia. Unlike women, who are equipped with their life's supply of eggs at birth, men replicate sperm from their bar mitzvah to their funeral. It's like a Xerox copy of a Xerox copy millions of times over. The damage can be caused by glitches in the process of replicating DNA millions of times over, reduced efficiency of the DNA repair mechanism, or attributed to environmental factors like stress, smoking or heavy drinking.

But the bottom line is: as men age, the percentage of damaged sperm they carry in their testes tends to increase. "Men are making millions of sperm all the time, and the chance for a copy error is much higher," says Dr. Ethylin Jabs, director of the Center for Craniofacial Development and Disorders at Johns Hopkins, who has conducted extensive research on paternal age and mutations within sperm. Where older women may be concerned about the viability of their remaining eggs, the problem for men, says Jabs, is "quantity not quality."

Semen samples of men over 45 showed impairment to sperm in three categories: their motility (swimming capability), vitality and DNA integrity, according to Dr. Sergey Moskovtsev of Mount Sinai Hospital's Department of Pathology and Laboratory Medicine in New York. Moskovtsev's research shows that men older than 45 have twice as much damage to their sperm as men under 30. Researchers believe that an increase in the percentage of damaged sperm can have a number of consequences.

A report released in PLoS Medicine last month establishes a link between reduced intelligence and children who were fathered by older men. Using a sample of 33,000 children tested at the ages of 8 months, 4 years and 7 years, John McGrath of Australia's Queensland Centre for Mental Health Research and colleagues found that children of older fathers ranked consistently lower in cognitive ability tests than the offspring of younger fathers. For example, 7-year-old children born to 50-year-old dads performed two IQ points lower than peers born to 20-year-old fathers. This difference in IQ is of course subtle, and McGrath says that the results of his study shouldn't be cause for individual men to stop having children.

But he cautions that the mounting studies pointing to a male biological clock are worth considering on a macro level. "As a researcher, I am concerned that we have neglected the issue of paternal age," McGrath says. "Worryingly, the mutations associated with advanced paternal age can be passed on to the next generation. As the population delays parenthood, these mutations could, theoretically, accumulate. Other researchers—not me—have called this process a 'mutational time-bomb'."

Normally, individual sperm with impaired DNA would perform a kind of cell hara-kiri, killing themselves in a process called apoptosis. But research out of the University of Washington has shown that the sperm of men over 35 are less likely to go through that process. Coupled with higher amounts of semen bearing damaged DNA, the likelihood of a child born with an abnormality increases. In a study of hundreds of thousands of psychiatric records conducted by the Israeli draft board in the 1980s, Dr. Abraham Reichenberg of the Mount Sinai School of Medicine, New York, and the Institute of Psychiatry, King's College London, and colleagues showed a six-time increase in autism spectrum disorders for children of fathers over 40, compared with those 29 years and younger.

Since that report came out in 2006, Reichenberg says that efforts to link autism and other psychological disorders to older dads have been bolstered by similar results among sample groups from different countries. Another psychological disorder that has been linked to damaged sperm is schizophrenia. Men over 50 are 3 times as likely to have offspring with the debilitating mental disorder than fathers under the age of 25....
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Monday, April 06, 2009

The Coming of the Daddy Wars

The Coming of the Daddy Wars
My favorite item from this week's Sunday papers was Lisa Belkin's Times Magazine piece on men's biological clocks. Belkin looks at new research showing that as men age beyond about 30, their chance of fathering a child with an autism-spectrum disorder or schizophrenia increases. Simultaneously, men's overall fertility decreases after age 35. Put simply, in the words of NYU psychiatry researcher Dr. Dolores Malaspina: “It turns out the optimal age for being a mother is the same as the optimal age for being a father.”

If these preliminary findings are upheld over time, their cultural significance -- especially for college-educated, type A, planner types -- could be huge. It isn't surprising that it has taken science this long to seriously question men's biological role in producing healthy children; we are all conditioned to see women as the folks primarily responsible for children, from conception through pregnancy, childbirth, and child-rearing. Young women know they are facing menopause down the road, and have often been warned by mothers and other older women about the difficulties of conception. As a consequence, it isn't uncommon to talk to women in their twenties who are aware of the latest trends on prenatal testing or fertility, but whose male partners have never bothered to inform themselves on such issues, even though they fully intend on having children "someday." As Belkin writes:

The push and pull between timetables and dreams, between our bodies and our babies, is at the core of many women’s worldview, which also means it is at the core of relationships between the sexes. This tension feeds the stereotype of woman as eager to settle down and men as reluctant, and it’s the crux of why we see women as “old” and men as “distinguished.”

Imagine a world in which the stereotype of women rushing men to the alter, biological clocks on overdrive, simply disappeared, as men took full 50 percent ownership over the reproductive process. Or in which wealthy 50- year old divorced men ceased to be such catches for 30-year old women, because of weakened sperm. I wouldn't want to return to a society in which both men and women are pressured into settling down and having babies at an unduly young age. But I do like the idea of rejiggering our notions about the intersection of gender and aging. It isn't just women who have a lot to fit into their lives in terms of career, romance, and parenthood. Science is beginning to tell us that men are facing the same pressures.

cross-posted at TAPPED

Wednesday, April 01, 2009

Lisa Belkin Audio on the Male Genetic Biological Clock

Lisa Belkin

Your Old Man

The Way We Live Now
Your Old Man
by LISA BELKIN
Published: April 1, 2009
Read between the lines of a recent study out of Australia and you can see hints of a coming shift in the gender conversation. Researchers at the University of Queensland found that children born to older fathers have, on average, lower scores on tests of intelligence than those born to younger dads. Data they analyzed from more than 33,000 American children showed that the older the man when a child is conceived, the lower a child’s score is likely to be on tests of concentration, memory, reasoning and reading skills, at least through age 7.



It was a small difference — just a few I.Q. points separated a child born to a 20-year-old and a child born to a 50-year-old. But it adds weight to a new consensus-in-the-making: there is no fountain of youth for sperm, no “get out of aging free” card. The little swimmers, scientists are finding, one study at a time, get older and less dependable along with every other cell in the male body.

And men don’t have to be all that old to be “too old.” French researchers reported last year that the chance of a couple’s conceiving begins to fall when the man is older than 35 and falls sharply if he is older than 40. British and Swedish researchers, in turn, have calculated that the risk of schizophrenia begins to rise for those whose fathers were over 30 when their babies were born. And another Swedish study has found that the risk of bipolar disorder in children begins to increase when fathers are older than 29 and is highest if they are older than 55. British and American researchers found that babies born to men over the age of 40 have significantly greater risk of autism than do those born to men under 30. (The age of the mother, in most of these studies, showed little or no correlation.)

Lay this latest I.Q. news atop the pile, and you find yourself reaching the same conclusion as Dr. Dolores Malaspina, a professor of psychiatry at New York University Medical Center, who has done some of the schizophrenia research: “It turns out the optimal age for being a mother is the same as the optimal age for being a father.”...

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