A pregnant mother's placenta can transmit damaging effects of stress to her unborn child, say researchers.
The impact is felt by a protein that affects the developing brains of boys and girls differently.
Scientists believe it could explain known links between maternal stress and disorders such as autism and schizophrenia, which are more common and serious in male offspring.
"Almost everything experienced by a woman during a pregnancy has to interact with the placenta in order to transmit to the foetus," said lead researcher Dr Tracy Bale, from the University of Pennsylvania's School of Veterinary Medicine in the US.
"Now we have a marker that appears to signal to the foetus that its mother has experienced stress."
The researchers studied female mice that were exposed to mild stresses such as the smell of foxes or unfamiliar noises during the first week of pregnancy.
They identified an enzyme called OGT that was present at lower levels in the placentas of stressed mice than in unstressed mice. Male offspring placentas also had lower natural levels of OGT than those attached to female offspring.
Further research showed that cutting levels of OGT triggered changes in more than 370 genes in the brains of unborn mice.
Many of these genes play a role in functions critical to neurological development, such as energy use, protein regulation and creating nerve cell connections.
The findings, reported in the journal Proceedings of the National Academy of Sciences, are likely to translate to humans, say the researchers.
Analysis of human placentas discarded after the birth of male babies showed evidence of reduced OGT levels.
The results suggest that OGT may protect the brain during pregnancy. Males have less of the protein to begin with, placing them at greater risk if their mothers are stressed.
Danger of Tokophobia
A debilitating phobia of pregnancy and childbirth left an already bereaved mother with no choice other than to abort her second baby. Tokophobia affects up to one in ten women, with some so fearful they liken maternity wards to torture chambers. Charlotte Arnold suffered so badly, she ended up aborting her second child because she was too scared to continue with the pregnancy. Read more <a href="http://www.huffingtonpost.co.uk/2012/11/28/tokophobia-the-debilitating-fear-pregnancy-birt-charlotte-arnold-abort-baby_n_2203223.html">here</a>.
Dieting In Pregnancy Could Be Beneficial
The common belief that pregnant women can eat for two has been scotched by research suggesting dieting during pregnancy can be beneficial. Experts found that weight management was not only safe but could also reduce complications for pregnant women and be advantageous to the baby. <a href="http://www.huffingtonpost.co.uk/2012/05/17/health-dieting-during-pregnancy-good_n_1523676.html" target="_hplink"><strong>Read the full story here</strong></a>.
Flu Shot In Pregnancy Prevents Stillbirth Risk
Canadian research has revealed that mothers who have flu shots during pregnancy reap unexpected health rewards for their babies. <a href="http://www.huffingtonpost.co.uk/2012/05/22/health-flu-shot-prevent-stillborn-baby_n_1535929.html?ref=uk-parenting " target="_hplink"><strong>Read the full story here</strong></a>.
Do You Think It's Safe To Jog While Pregnant?
When six-month pregnant Jenny Wright was called a 'selfish cow' while out for a run in Leeds' Roundhay Park, she assumed she'd misheard. <a href="http://www.huffingtonpost.co.uk/2012/05/14/health-selfish-cow-jogging-mum-baby_n_1514920.html?ref=uk-parenting" target="_hplink"><strong>Read the full story here</strong></a>.
Pregnant Dieters More Likely To Have An Obese Child
Women who fall pregnant while dieting are more likely to have a child that could become obese or diabetic in later life, new research suggests. <a href="http://www.huffingtonpost.co.uk/2012/04/02/pregnant-diet-obese-baby-unborn-baby-diabetes-pill_n_1396151.html?ref=uk-parenting" target="_hplink"><strong>Read the full story here</strong></a>.
Why Women Take Two Hours Longer To Give Birth Than Their Grandmothers
Pregnant women are spending more time in labour now than 50 years ago, a recent study has discovered. <a href="http://www.huffingtonpost.co.uk/2012/04/02/women-take-longer-to-give-birth-than-50-years-ago_n_1396373.html?ref=uk-parenting" target="_hplink"><strong>Read the full story here</strong></a>.
1000 Photo Pregnancy Is YouTube Hit
Most women probably wish they could get their nine months of pregnancy in four minutes - even if it would leave only a few seconds to decorate the nursery, but at least morning sickness is over in a millisecond. Osher Grencel's pregnancy appears to be happening at the speed of light as husband Tomer took more than 1000 photographs of her in comfy tracksuit bottoms and a white crop top as her pregnant belly grows, morning sickness passes and cribs and prams bought. Read more <a href="http://www.huffingtonpost.co.uk/2012/11/25/osher-tomer-grencel-pregnancy_n_2188063.html">here</a>.
Eating Unhealthy Food Linked To Lower Birth Weight
Eating chips during pregnancy can lead to significant health problems for new born babies, research suggests. Consuming a vast quantity of chips, crisps and biscuits during pregnancy can lead to babies having a lower than average birth weight, the study found. Mothers-to-be who have a high intake of acrylamide - which is found in commonly consumed foods and coffee - are also more likely to have a baby which has a smaller head circumference. Read more <a href="http://www.huffingtonpost.co.uk/2012/10/23/unhealthy-food-chips-lower-birth-rate-babies_n_2004643.html">here</a>.
"We want to get to the point where we can predict the occurrence of neurodevelopmental disease," said Dr Bale.
"If we have a marker for exposure, we can meld that with what we know about the genetic profiles that predispose individuals to these conditions and keep a close eye on children who have increased risks."
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Bring Your Dog To Work
A recent study in the <em>International Journal of Workplace Health Management</em> showed that <a href="http://www.huffingtonpost.com/2012/04/01/bringing-dog-to-work-stress_n_1391420.html" target="_hplink">bringing your dog to work</a> could help to lower office stress and boost employee satisfaction. "Pet presence may serve as a low-cost, wellness intervention readily available to many organizations and may enhance organizational satisfaction and perceptions of support," study researcher Randolph T. Barker, Ph.D., a professor of management at Virginia Commonwealth University, said in a statement. "Of course, it is important to have policies in place to ensure only friendly, clean and well-behaved pets are present in the workplace." The study, which looked at the pet-friendly company Replacements, Ltd., showed that employees who brought their dogs in to work experienced <a href="http://www.huffingtonpost.com/2012/04/01/bringing-dog-to-work-stress_n_1391420.html" target="_hplink">decreases in stress</a> throughout the work day. Meanwhile, self-reported stress <em>increased</em> for people who didn't bring their dogs, and for those who don't have dogs.
Laugh It Up
If you're feeling particularly stressed, perhaps it's time to take a quick YouTube break. A small 1989 study in the <em>American Journal of the Medical Sciences</em> showed that<a href="http://www.ncbi.nlm.nih.gov/pubmed/2556917" target="_hplink"> "mirthful laughter"</a> is linked with lower blood levels of the stress hormone cortisol. The Mayo Clinic reported that laughter also promotes <a href="http://www.mayoclinic.com/health/stress-relief/SR00034" target="_hplink">endorphin release</a> in the brain and relaxes the muscles, which are all key for stress relief.
Grab A Shovel And Some Seeds
Caregiving is extremely stressful, but a 2008 survey showed that gardening may help to reduce stress among caregivers. The survey, by BHG.com, showed that 60 percent of caregivers feel <a href="http://www.alz.org/national/documents/release_110308_garden.pdf" target="_hplink">relaxed when they garden</a>, the Alzheimer's Association reported. And, Health.com reported on a Netherlands study, suggesting that gardening can help to <a href="http://www.health.com/health/article/0,,20507878_2,00.html" target="_hplink">lower cortisol levels</a> and boost mood among people who had just finished a stressful task. That's because doing something that requires "involuntary attention" -- like sitting back and enjoying nature -- helps to replenish ourselves, Health.com reported.
Crack Open A Book
Just <a href="http://www.telegraph.co.uk/health/healthnews/5070874/Reading-can-help-reduce-stress.html" target="_hplink">six minutes of reading</a> is enough to help you de-stress, the <em>Telegraph</em> reported. The study, which was sponsored by Galaxy chocolate, suggested that <a href="http://www.telegraph.co.uk/health/healthnews/5070874/Reading-can-help-reduce-stress.html" target="_hplink">reading was linked with a slower heart rate</a> and muscle relaxation. Drinking tea or coffee, listening to music and taking a walk also seemed to help lower stress, according to the <em>Telegraph</em>.
Even if she's not there in person, a call to mom can help lower stress. <em>Scientific American</em> reported on a study in the journal <em>Proceedings of the Royal Society B</em> showing that young girls who <a href="http://blogs.scientificamerican.com/observations/2010/05/11/a-phone-call-from-mom-reduces-stress-as-well-as-a-hug/" target="_hplink">talked to their mothers on the phone</a> after completing stressful tasks had decreased cortisol (the stress hormone) in their saliva, and increased oxytocin levels (the bonding hormone). The girls who talked to their mothers on the phone had <a href="http://blogs.scientificamerican.com/observations/2010/05/11/a-phone-call-from-mom-reduces-stress-as-well-as-a-hug/" target="_hplink">decreased cortisol</a> and increased oxytocin levels compared with young girls who weren't allowed to contact their mothers at all, <em>Scientific American</em> reported -- girls who hugged their moms in person had a similar reaction to the phone group.
Eat Some Chocolate
Dark chocolate doesn't only have health benefits for the heart -- eating it can also help to <a href="http://www.livescience.com/7974-chocolate-reduces-stress-study-finds.html" target="_hplink">lower stress</a>. LiveScience reported on a study illustrating that eating 1.4 ounces of <a href="http://www.livescience.com/7974-chocolate-reduces-stress-study-finds.html" target="_hplink">dark chocolate</a> a day for a two-week period is linked with decreased levels of the stress hormone cortisol. That study was published in 2009 in the journal <em>Proteome Research</em>. (But of course, chocolate still contains sugar and lots of calories, so make sure you're eating the chocolate in moderation!)
Gossip may not be viewed as socially "good," but it <em>might</em> have benefits in relieving stress. Researchers from the University of California, Berkeley, found that <a href="http://www.huffingtonpost.com/2012/01/17/gossip-stress-exploitation-heart-rate_n_1211207.html" target="_hplink">gossiping can actually lower stress</a>, stop exploitation of others and police others' bad behavior. "Spreading information about the person whom they had seen behave badly tended to <a href="http://www.huffingtonpost.com/2012/01/17/gossip-stress-exploitation-heart-rate_n_1211207.html" target="_hplink">make people feel better</a>, quieting the frustration that drove their gossip," study researcher Robb Willer, a social psychologist at UC Berkeley, said in a statement. Willer's research was published this year in the <em>Journal of Personality and Social Psychology</em>. So if something's bothering you, go ahead and gab -- but just make sure you move on so you don't dwell on the negative emotions!