Dr. Onyeije’s Maternal-Fetal Medicine Blog

Will all babies get tested for autism in the womb?

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British researchers have identified up to 300 genes that cause autism, and they hope to have mapped all the genes responsible for the condition within two years. And they believe that eventually, all newborn children could be tested for autism.

A group of Oxford researchers, writing in the journal Nature, say that they've identified several new genes that could help create a predisposition for autism, and they hope to identify all of the genes involved in the condition within the next two years. The newly identified genes relate to things like connections between brain cells, and signaling between brain cells. This makes autism seem more like a genetic condition — and it seems much less likely that vaccinating your children causes them to become autistic.

Talking to the BBC, the researchers hold out the promise that eventually their research could lead to more drug therapies for autism, but that's probably a long way off. More immediately, though, their findings are giving us more insight into the origins of this condition, which may spring from the interaction of these genes with the child's environment.

And Oxford professor Tony Monaco seems confident that we could have a genetic test for susceptibility to autism pretty soon. He tells the BBC:

"The idea is to track these genes in their families and see if we can offer genetic counselling and what information we can offer the patient. If we can show the efficacy of that in the clinical care of the patients then we can push for it into genetic testing in the NHS. We'd hope that within two years we'd come up with clinical practice guidelines. So families can expect that we might be able to offer in the very near future some further DNA analysis of all patients."

Monaco seems to be referring to testing newborns for a susceptibility to autism before they actually develop the condition, which could allow for more counseling and possibly some early treatments. But his remarks also raise the specter that parents could get tested before conceiving, to see if their genes might lead to a child with a tendency to autism. Or we could start routinely testing embryos for autism in the womb.

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Slightly early births linked to autism, dyslexia

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Babies born just 1 or 2 weeks before their 40-week gestation due date are more likely to develop learning difficulties such as autism or dyslexia, according to a British study published on Tuesday.

The findings show that even babies born at 39 weeks -- the point at which many women who choose to have a Cesarean section delivery -- have an increased risk of a developing a learning disability compared with babies born a week later at 40 weeks.

Scientists in Scotland, analyzing the birth history of more than 400,000 schoolchildren, found that while babies born at 40 weeks have a 4 percent risk of learning difficulties, those born at 37 to 39 weeks of gestation have a 5.1 percent risk.

It is already known that a baby born prematurely -- for example at 24 weeks of gestation -- is more likely to have learning difficulties. But the risks for babies born in the 24 to 40 week range had not previously been studied.

Around a third of babies are born between 37 and 39 weeks of gestation, either by cesarean section or natural vaginal delivery.

Pell, whose study was published in the Public Library of Science Medicine journal, stressed that cesarean sections were not the only factor behind early-term births, since some women go into labor naturally before 40 weeks of gestation.

But she said doctors and women should consider the risks of learning difficulties when thinking about a cesarean.

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Infants Recognize Voices, Emotions By 7 Months

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A new study suggests that our brains develop specialized circuits to process human voices long before we learn to speak.

The study, which appears in the journal Neuron, looked at brain activity in 32 infants as they listened to recorded sounds. Half the children were 4 months old and the other half were 7 months old.

Some of the sounds they heard were nonhuman sounds, like chickens clucking, a bell ringing or a cuckoo clock. The rest were clearly human utterances including some words, though not in any language the children would have heard before.

While the children listened, researchers from Germany and the U.K. measured activity in certain areas within a part of the brain called the superior temporal cortex, which is just above the ear. Other studies have shown that these areas are where voices are processed in adults.

In 4-month-old infants, these areas did not differentiate between human voices and nonhuman sounds, says Tobias Grossman from the Centre for Brain and Cognitive Development at the University of London and the Max Planck Institute for Human Cognitive and Brain Sciences.

But it was a different story in the 7-month-old infants, Grossman says. The brain responses showed that "they process human voice distinctly from other kinds of sounds," he says.

The researchers wanted to know whether the older children's brains would also respond to the emotional meaning that's often conveyed through vocal intonation.

So they played unfamiliar words spoken with happy, unhappy and neutral intonations, and once again, certain areas of the brain seemed to know the difference.

The findings provide strong evidence that specialized voice processing in the brain develops sometime between the fourth and seventh month of life, Grossman says.

Problems with the brain systems that recognize and process human voices could offer an early warning of language difficulties.

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1 in 4 Parents Link Autism to Vaccines

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Most parents believe that vaccines protect their children against disease, but one in four think some vaccines cause autism in healthy children, and nearly one in eight have refused at least one recommended vaccine, a new study has found.

The vaccine most likely to have been rejected by parents was for human papillomavirus, or HPV, to protect against cervical cancer, according to the report. It was based on questions asked of more than 1,500 parents of children 17 and younger. Many parents also rejected the chickenpox vaccine, the meningococcal conjugate vaccine against bacterial meningitis and, to a lesser extent, the MMR, which protects against measles, mumps and rubella.

Just last month, the British medical journal The Lancet retracted the 1998 study that first linked the MMR vaccine to autism and set off widespread fears about vaccine safety.

“We were sobered to find that one in four parents erroneously believe that vaccines can cause autism in an otherwise healthy child,” said Dr. Gary L. Freed, a professor of pediatrics at the University of Michigan and the lead author of the paper, published online on March 1 by the journal Pediatrics. “Fortunately, they are still overwhelmingly vaccinating their children.”

Nine of 10 parents agreed that vaccines protected children from disease, but more than half said they were concerned about serious adverse effects.

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Wanted: Volunteers, All Pregnant

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The woman sent by government scientists visited the Queens apartment repeatedly before finding anyone home. And the person who finally answered the door - a 30-year-old Colombian-born waitress named Alejandra - was wary.

Although Alejandra was exactly what the scientists were looking for - a pregnant woman - she was "a bit scared," she said, about giving herself and her unborn child to science for 21 years.

Researchers would collect and analyze her vaginal fluid, toenail clippings, breast milk and other things, and ask about everything from possible drug use to depression, At the birth, specimen collectors would scoop up her placenta and even her baby’s first feces for scientific posterity.

She ultimately decided that participating would “help the next generation.”

Chalk one up for the scientists, who for months have been dispatching door-to-door emissaries across the country to recruit women like Alejandra for an unprecedented undertaking: the largest, most comprehensive long-term study of the health of children, beginning even before they are born.

Authorized by Congress in 2000, the National Children’s Study began last January, its projected cost swelling to about $6.7 billion. With several hundred participants so far, it aims to enroll 100,000 pregnant women in 105 counties, then monitor their babies until they turn 21.

It will examine how environment, genes and other factors affect children’s health, tackling questions subject to heated debate and misinformation. Does pesticide exposure, for example, cause asthma? Do particular diets or genetic mutations lead to autism?

But while the idea is praised by many experts, the study has also stirred controversy over its cost and content.

In August, the Senate committee overseeing financing for the study accused it of “a serious breach of trust” for not disclosing that the initial price tag of $3.1 billion would more than double, and said the study needed to release more information if it wanted to get “any” financing in the next budget year.

And an independent panel of experts and some members of the study’s own advisory committee say it misses important opportunities to help people and communities — emphasizing narrower medical questions over concerns like racial and ethnic health differences, leaving unresolved crucial ethical questions concerning what to tell participants and communities about test results.

“This study is of the magnitude of the accelerator in CERN, or a trip to the moon — a really big science issue,” said Milton Kotelchuck, a professor at the Boston University School of Public Health and a member of the independent panel. “But if you have a flawed beginning, then you’ve got 20 years of working on a flawed study.”

Officials are making changes, putting all but the pilot phase, to involve 37 locations, on hold while conducting an inquiry into the cost and scientific underpinnings, Dr. Collins said. Some data may no longer be collected if “we can’t afford” it, he said, and every aspect will receive “the closest possible scrutiny.”

The study is far from its plan of recruiting 250 babies a year for four or five years in each community. By December, 510 women were enrolled and 83 babies were born in the first seven locations, including Orange County, Calif., and Salt Lake County, Utah.

That was after knocking on nearly 64,000 doors, screening 27,000 women and finding 1,000 who were pregnant and in their first trimester (and therefore eligible).

The time and information required from families could also make the study “too burdensome to be conducted the way it is,” said Dr. Susan Shurin, former acting director of the National Institute of Child Health and Human Development, part of the National Institutes of Health and the study’s supervising agency. The fear is women will “go ‘Oh no, you again,’ and slam the door in your face.”

Specimens include blood, urine, hair and saliva from pregnant women, babies and fathers; dust from women’s bedsheets; tap water; and particles on carpets and baseboards. They are sent to laboratories (placentas to Rochester, N.Y., for example), prepared for long-term storage, and analyzed for chemicals, metals, genes and infections.

Participants provide the names and phone numbers of relatives and friends, so researchers can find them if they move. As children grow, scientists, including outside experts, can cross-reference information about their medical conditions, behavioral development and school performance.

Besides looking at widespread conditions, like diabetes, the study will consider regional differences. Maureen Durkin, principal investigator in Waukesha County, Wis., wonders if radium in the county’s water, and houses built on “farm fields that may be contaminated with nitrates and atrazine,” have different health consequences than pollution or industrial chemicals in Queens.

But study officials are trying to determine what information to give participants and when. Some experts say people should get results of their chemical or genetic tests only if medical treatments exist because otherwise it only causes anxiety. Others agree with Patricia O’Campo, a member of the study’s advisory committee and the independent panel, who says the study should be “less ivory towerish” and disclose more information to families and communities.

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Older mothers’ kids have higher autism risk, study finds

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A 10-year study examining 4.9 million births in the 1990s has found more evidence that there's a link between autism and the mother's age at conception.

The link between the parents' age and children's health is not entirely new. Prior studies have indicated that babies born to older women have higher risks of birth defects, low birth weight and certain chromosome problems, such as Down syndrome.

A 2007 Kaiser Permanente study conducted in California reported that autism risk increased with both the mother's and father's age. An Israeli study based in statistics from 1980s had isolated only paternal age as being linked with increased risk for autism.

Dr. Max Wiznitzer, a pediatric neurologist at Rainbow Babies & Children's Hospital in Cleveland, Ohio, said the latest research had a far larger sample size.

In the latest study, researchers found that mothers over the age of 40 had 51 percent higher odds of having children with autism compared with mothers between the ages 25 and 29.

The father's age also played a factor, but only when he had a child with a woman under 30.

"When the mom has minimal age risk of an autistic child, we do see increased risks as dads get older," said lead author Janie Shelton, a graduate student researcher at UC-Davis.

It's unclear why the mother's age has more bearing in autism risk than the father's.

The study authors emphasize that while autism rates have risen 600 percent in the past two decades, older women having children contributed to only 5 percent more cases of autism.

As more women delay childbearing, it's important to keep the study in perspective, said Geraldine Dawson, chief science officer of Autism Speaks, the nation's largest autism science and advocacy organization.

"I don't think a mom blaming herself is going to help us understand what's causing autism or help prevent further cases," she said. "I would urge parents not to blame themselves, regardless of what age they are."

Shelton and the co-authors obtained all birth records in California from 1990 to 1999 and then collected data from the state's Department of Developmental Services to count the number of autism diagnoses from children born during that decade.

How parental age increases autism risks remains unknown, but several hypotheses exist. Some suggest that the cumulative effects of the environment, changes to the autoimmune system, stress and reproductive technology may affect autism risk.

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Aspirin During Pregnancy May Help Preemies

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The children of women who take low-dose aspirin during pregnancy because they are at high risk for delivering prematurely might have fewer behavioral problems at age 5, new research suggests.

Obstetricians sometimes give low-dose aspirin to pregnant women who are apt to have such complications as fetal growth restriction (when a fetus doesn't grow properly in the womb) or preeclampsia (high blood pressure that's dangerous to both mother and the fetus), said Dr. Ashley Roman, a clinical assistant professor of obstetrics and gynecology at NYU Langone Medical Center. Roman was not involved in the research.

In the study, French researchers used data on 656 children born before 33 weeks of gestation to 584 women from nine regions in France. A full-term birth is at 40 weeks' gestation. The women had a history of placental vascular disease, fetal growth restriction, chronic hypertension, and renal or autoimmune diseases.

About 21 percent of the women took low-dose aspirin during pregnancy.

At age 5, children whose mothers had taken aspirin were slightly less likely to have behavioral difficulties or hyperactivity, though the results were not statistically significant, according to the study.

In addition, the babies whose mothers had taken aspirin faced no increased risk for death, cerebral lesions or cerebral palsy.

One of the fears of giving aspirin to women during pregnancy is that aspirin interferes with platelet function, which is important for blood clotting. Because of that, it could raise the risk for brain bleeds in already susceptible premature infants, Roman said. The study found no increase in the risk for brain bleeds.

The study findings are published online Dec. 21 and in the January print issue of the journal Pediatrics.

Still, much remains unknown about the role of aspirin in pregnancy, including exactly how well or why aspirin works, Roman noted. One theory is that fetal growth restriction might be caused by tiny blood clots in the placenta, and aspirin helps blood flow between the placenta and the fetus. Low-dose aspirin is also taken by adult men and women at risk for heart attack and stroke.

Dr. Michael Katz, senior vice president for research and global programs at the March of Dimes, said the study is intriguing, but the findings are too preliminary to be of much help to women or their physicians. Many women in the study were also given other drugs, including corticosteroids, and it's unknown how much that affected the outcomes.

"Behavioral difficulties," as cited in the study, is a broad term that could encompass everything from excessive temper tantrums to learning disabilities to hyperactivity to autism, he said, each of which could have very different underlying causes.

Premature babies are at higher risk for neurological problems, including learning disabilities, cerebral palsy, and hearing and vision problems.

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