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There has been much discussion lately on declining male sperm counts and what it means. From Medical Xpress:

No link found between low sperm count, birth defects

Having a low sperm count doesn't seem to determine whether a man's children will be born with birth defects, a new study indicates.

With infertile couples, men are partially or fully responsible for the inability to conceive about 40 percent of the time. Assisted reproductive technologies such as in vitro fertilization can help couples have children, but research has suggested a possible link between these approaches—when used to treat infertility problems in the male partner—and a higher risk of birth defects.

In the new study, researchers examined a Baylor College of Medicine database in search of possible connections between birth defects and low sperm count. The researchers didn't find any links.

But the following finding is a cause for concern. From Science Daily:

Male infertility linked to mortality, study shows

Men who are infertile because of defects in their semen appear to be at increased risk of dying sooner than men with normal semen, according to a study. Men with two or more abnormalities in their semen were more than twice as likely to die over a roughly eight-year period as men who had normal semen, the study found.

Several interesting bacteria studies. Who knew that dental caries (tooth decay that causes cavities) is contagious? From Science Daily:

Bacteria can linger on airplane surfaces for days

Disease-causing bacteria can linger on surfaces commonly found in airplane cabins for days, even up to a week, according to research. In order for disease-causing bacteria to be transmitted from a cabin surface to a person, it must survive the environmental conditions in the airplane. In this study, MRSA lasted longest (168 hours) on material from the seat-back pocket while E. coli O157:H7 survived longest (96 hours) on the material from the armrest.

From Science Daily: Cavities are contagious, research shows

Dental caries, commonly known as tooth decay, is the single most common chronic childhood disease. In fact, it is an infectious disease, new research demonstrates. Mothers with cavities can transmit caries-producing oral bacteria to their babies when they clean pacifiers by sticking them in their own mouths or by sharing spoons. Parents should make their own oral health care a priority in order to help their children stay healthy.

From Science Daily: Physicians' stethoscopes more contaminated than palms of their hands

Although healthcare workers' hands are the main source of bacterial transmission in hospitals, physicians' stethoscopes appear to play a role. To explore this question, investigators assessed the level of bacterial contamination on physicians' hands and stethoscopes following a single physical examination. Two parts of the stethoscope (the tube and diaphragm) and four regions of the physician's hands (back, fingertips, and thenar and hypothenar eminences) were measured for the total number of bacteria present in a new study. The stethoscope's diaphragm was more contaminated than all regions of the physician's hand except the fingertips. Further, the tube of the stethoscope was more heavily contaminated than the back of the physician's hand.

Another reason to breastfeed infants. From Medical Xpress:

Breastfeeding promotes the growth of beneficial bacteria in the gut

A number of studies have shown that breastfed babies grow slightly slower and are slightly slimmer than children who are fed with infant formula. Children who are breastfed also have a slightly lower incidence of obesity, allergies, diabetes and inflammatory bowel disease later in life. According to a new study by the National Food Institute and the University of Copenhagen this may be due to the fact that breastfeeding promotes the development of beneficial bacteria in the baby's gut.

"We have become increasingly aware of how crucially important a healthy gut microbial population is for a well-functioning immune system. Babies are born without bacteria in the gut, and so it is interesting to identify the influence dietary factors have on gut microbiota development in children's first three years of life," research manager at the National Food Institute Tine Rask Licht says.

The study shows that there are significant changes in the intestinal bacterial composition from nine to 18 months following cessation of breastfeeding and other types of food being introduced. However, a child's gut microbiota continues to evolve right up to the age of three, as it becomes increasingly complex and also more stable.

"The results help to support the assumption that the gut microbiota is not - as previously thought - stable from the moment a child is a year old. According to our study important changes continue to occur right up to the age of three.

More information: The study has been described in a scientific article in Applied and Environmental Microbiology: Establishment of intestinal microbiota during early life: A longitudinal, explorative study of a large cohort of Danish infants:www.ncbi.nlm.nih.gov/pubmed/24584251

Since myopia increased 66% between the early 1970s to early 2000s in the United States, it is thought that there are environmental factors at play, namely higher levels of education, all our close-up activities with new technology (reading, computers, tablets, etc.) straining our eyes, and spending too much time indoors. From The Atlantic:

Nearsightedness and the Indoor Life

Over the past 15 years, the world has witnessed an explosion of cases of myopia, or nearsightedness. A quarter of the world's population, or 1.6 billion people, now suffer from some form of myopia, according to the Myopia Institute. If unchecked, those numbers are estimated to reach one-third of the world's population by 2020. 

The 2009 study is hardly the first to suggest that an increase in years of formal education and access to technology across society may account for higher myopia rates in recent years. Ophthalmologists and optometrists have cautioned that close-up activities like reading and using computers, tablets, and smartphones interfere with normal blinking and put a strain on the eyes. When abused, they can lead to double vision, myopia, and serious conditions such as retinal detachment and vision loss. The overuse of handheld electronics such as iPads and tablets by young children is especially worrisome, since their eyes are still developing and are more likely to be affected, according to researchers.

Kathryn Rose, a researcher of visual disorders at the University of Sydney's college of health sciences, recently concluded  that spending too much time indoors also has a huge impact on eyesight deterioration. Rose said in a CNN interview that she was not sure how time spent using digital media relates to myopia progress, but that outdoor light has been shown to have a positive effect on vision. Studies from the U.S., Singapore, and China confirm a link between the time spent outdoors and the prevention of myopia, Rose said. However, both the level of light and the duration of exposure to outdoor light must reach a certain threshold to have a preventive effect, according to one of her studies. Spending at least 10 to 14 hours outside per week may prevent the early onset of myopia, she concluded.

Dr. Maria Liu, head of the Myopia Control Clinic that opened last year, explained that prevention and treatment success depend on early detection. Nearsighted children under 10 could benefit the most from intervention. This age group is also the most susceptible to eye damage from prolonged use of visual media, according to the myopia specialist."The eyeballs are very adaptive while they are developing," Liu told me. "If we impose a lot of near work on the eyes as they are developing, the eyes will interpret nearsightedness as being the normal state."

She explained the rise in myopia prevalence is likely caused by a shift in lifestyle from spending time outdoors to an indoor-oriented existence. Electronic devices play a major role in this shift, especially with young children being introduced to technology at an earlier stage in their life, and using handheld devices that require a smaller working distance than that for a physical book or television.

The Myopia Control Clinic specialists use corrective lenses (novel contact lenses) to slow down myopia in children. If applied early enough, corrective lenses have proven effective in treating the disorder. In cases with very high myopia progression, however, scleral reinforcement surgery is used to reduce or stop further damage caused by high myopia, which often can be degenerative. Atropine is the only drug that so far has proven effective in slowing myopia progression. The drug is used as a second line of treatment after all optical treatments fail.

Although modern lifestyle makes it harder to fight the disorder, there is something parents can do to prevent its early onset."Whether it is because hormonal levels are different outdoors, or because the light intensity is stronger, or because we do less close-up work, it has been shown consistently that outdoor activity is very protective and tends to slow the rate of progression."

Taking frequent 10-minute breaks from near-work and looking in the distance is also recommended, including for young adults who spend a lot of time working on computers or laptops and may suffer from accommodating spasms that cause blurry distance vision and dry eyes. Some specialists recommend limiting time in front of computers, TVs, and handheld devices to 1.5 hours a day, especially for young children.

Excerpts from a very interesting NPR interview with Dr. Martin Blaser and his views on the human microbiome. His recently published book is Missing Microbes: How the Overuse of Antibiotics is Fueling Our Modern Plagues. From NPR News:

Modern Medicine May Not Be Doing Your Microbiome Any Favors

There are lots of theories about why food allergies, asthma, celiac disease and intestinal disorders like Crohn's disease have been on the rise. Dr. Martin Blaser speculates that it may be connected to the overuse of antibiotics, which has resulted in killing off strains of bacteria that typically live in the gut.

Blaser is an expert on the human microbiome, which is the collection of bacteria, viruses, fungi and other microbes that live in and on the body. In fact, up to 90 percent of all the cells in the human body aren't human at all — they're micro-organisms. Blaser is the director of NYU's Human Microbiome Program and a former chairman of medicine there. His new book is called Missing Microbes: How the Overuse of Antibiotics Is Fueling Our Modern Plagues.

"Since World War II, we've seen big rises in a number of diseases: asthma, allergies, food allergies, wheat allergy, juvenile diabetes, obesity. ... These are all diseases that have gone up dramatically in the last 50 or 70 years. One of the questions is: Why are they going up? Are they going up for 10 different reasons, or perhaps there is one reason that is fueling all of them."

"My theory is that the one reason is the changing microbiome; that we evolved a certain stable situation with our microbiome and with the modern advances of modern life, including modern medical practices, we have been disrupting the microbiome. And there's evidence for that, especially early in life, and it's changing how our children develop."

"There's a choreography; there's a normal developmental cycle of the microbiome from birth over the first few years of life, especially the first three years, [that] appear[s] to be the most important. And that's how nature has, how we have, evolved together so that we can maximize health and create a new generation, which is nature's great purpose. And because of modern practices, we have disrupted that. And then the question is: Does that have consequence[s]?"

"As far as we know, when the baby is inside the womb it is apparently sterile. ... The big moment of truth is when the membranes rupture, the water breaks, and the baby starts coming out. And that's where they first get exposed to the bacteria of the world, and the first bacteria they're exposed to is their mother's bacteria in the birth canal. So as labor proceeds, the babies are in contact with the microbes lining their mother's vagina and, as they're going out, they're covered by these bacteria. They swallow the bacteria; it's on their skin. ..."

"That's their initial exposure to the world of bacteria. That's how mammals have been doing it for the last 150 million years, whether they're dolphins or elephants or humans. ... And we know a little about what those bacteria are. The most common bacteria are lactobacillus and there's evidence that over the course of pregnancy the microbiome in the vagina changes, just as many other parts of the body are changing. The microbiome is changing in its composition in terms of maximizing lactobacilli, and these are bacteria that eat lactose, which is the main component of milk. So the baby's mouth is filled with lactobacilli. The first thing that happens is they go up against their mom's breast and they inoculate the nipple with lactobacilli and now milk and lactobacilli go into the new baby and that's the foundation for their microbiome and that's how they start their life. ..."

"You could project that if they didn't acquire these organisms or they didn't acquire them normally or at the normal time, then the foundations might be a little shaky."

"Shortly after birth, they compared the microbiomes in the babies that came out. The babies that were born vaginally, their microbiome, not surprisingly, looked like the mom's vagina everywhere in the body — in their GI tract, on their skin, in their mouth. But the babies born by C-section, their microbiome looked like skin and it didn't even necessarily look like the mom's skin, maybe it was somebody else in the operating room. So it's clear that the microbiome is different immediately depending on the kind of birth."

"What I can tell you is that our immune system is quite complex. There are many kinds of immune cells. There are cells that strongly recognize foreign substances, there are ones that try to damp [the immune system] and down-regulate it. There's what we call innate immunity, which is the immunity we're all born with, and then there's adaptive immunity — the immunity that develops when we experience different kinds of exposures. So it's very complex."

"There are many different probiotics.  I think I can say three things: The first is that they're almost completely unregulated; second is that they seem to be generally safe; and third is that they're mostly untested. ... I'm actually a big believer in probiotics; I think that's going to be part of the future of medicine, that we're going to understand the science of the microbiome well enough so that we can look at a sample from a child and say this child is lacking such-and-such an organism and now we're going to take it off the shelf and we're going to give it back to that child. ... "

An argument for the need for human exposure to the microbes in rural environments. However, the role of diesel exhaust and other urban air pollutants is not discussed here (for example, diesel exhaust is linked to asthma). From Science Daily:

Rural microbes could boost city dwellers' health, study finds

The greater prevalence of asthma, allergies and other chronic inflammatory disorders among people of lower socioeconomic status might be due in part to their reduced exposure to the microbes that thrive in rural environments, according to a new scientific paper co-authored by a University of Colorado Boulder researcher.

The article, published in the journal Clinical & Experimental Immunology, argues that people living in urban centers who have less access to green spaces may be more apt to have chronic inflammation, a condition caused by immune system dysfunction.

When our immune systems are working properly, they trigger inflammation to fight off dangerous infections, but the inflammation disappears when the infection is gone. However, a breakdown in immune system function can cause a low level of inflammation to persist indefinitely. Such chronic inflammation can cause a host of health disorders.

Some scientists have hypothesized that the increase of chronic inflammation in wealthier Western countries is connected to lifestyles that have essentially become too clean. The so-called "hygiene hypothesis" is based on the notion that some microbes and infections interact with the immune system to suppress inflammation and that eliminating exposure to those things could compromise your health.

The authors agree that microbes and some types of infections are important because they can keep the immune system from triggering inflammation when it's not necessary, as happens with asthma attacks and allergic reactions.

But they say the infections that were historically important to immune system development have largely been eliminated in developed countries. The modern diseases we pick up from school, work and other crowded areas today do not actually lead to lower instances of inflammatory disorders.

During our evolutionary history, the human immune system was exposed to microbes and infections in three important ways: commensal microbes were passed to infants from their mothers and other family members; people came into contact with nonpathogenic microbes in the environment; and people lived with chronic infections, such as helminths, which are parasitic worms found in the gut and blood.

In order for those "old infections" to be tolerated in the body for long periods of time, they evolved a mechanism to keep the human immune system from triggering inflammation. Similarly, environmental bacteria, which were abundant and harmless, were tolerated by the immune system. According to Rook, a professor at UCL, "Helminthic parasites need to be tolerated by the immune system because, although not always harmless, once they are established in the host efforts by the immune system to eliminate them are futile, and merely cause tissue damage."

In contrast, relatively modern "crowd infections," such as measles or chicken pox, cause an inflammatory response. The result is that either the sick person dies or the infection is wiped out by the inflammation and the person becomes immune from having the same infection again in the future.

Collectively, the authors refer to the microbes and old infections that had a beneficial impact on the function of our immune systems as "old friends." Exposure to old friends plays an important role in guarding against inflammatory disorders, the authors said. Because the "old infections" are largely absent from the developed world, exposure to environmental microbes -- such as those found in rural environments, like farms and green spaces -- has likely become even more important.

The authors say this would explain why low-income urban residents -- who cannot easily afford to leave the city for rural vacations -- are more likely to suffer from inflammatory disorders. The problem is made worse because people who live in densely populated areas also are more likely to contract crowd infections, which cause more inflammation.

The controversy over the safety of BPA (bisphenol A) is still dragging on. However, the new alternatives to BPA may not be any better and may be even worse. To minimize exposure to BPA and other estrogenic chemicals, try to buy and store food in glass bottles, jars, and containers (glass does not contain plastics of any sort). The following two articles discuss this issue. From Nature:

Toxicology: The plastics puzzle

A stroll down the aisles of a US supermarket reveals a modest victory for consumer activism. In the baby-products section, plastic baby bottles, spill-proof cups and miniature cutlery are proudly marked 'BPA-free' — a sign that they no longer contain the compound bisphenol A, found in many plastics.

The partial withdrawal of BPA is the culmination of two decades of research and hundreds of studies linking the compound — which mimics sex hormones called oestrogens — to adverse health effects in rodents and humans.  The decision by regulators in the United States and European Union to ban BPA from baby bottles, combined with industry marketing campaigns, has convinced many consumers that the plastics and other containers currently used to store food are safe.

It is a false sense of security. BPA is still a constituent of many food containers, especially cans. And when companies did abandon BPA, they often adopted compounds — such as the increasingly common bisphenol S (BPS) — that share much of the same chemistry and raise many of the same concerns as BPA. “People use this chemical to replace BPA without sufficient toxicological information,” says Kyungho Choi, an environmental toxicologist at Seoul National University. “That is a problem.”

BPA has formed the chemical backbone of most hard, clear polycarbonate plastic since the 1950s. Over time, studies have linked the chemical — which can leach out of plastics and into food — to a host of adverse health effects, including reductions in fertility and birth weight, male genital abnormalities, altered behavioural development, diabetes, heart disease and obesity1 (see Nature46411221124; 2010).

A few years ago, mounting evidence and concerned consumers convinced governments to take action. In 2011, the European Union banned BPA from baby bottles; the United States followed suit a year later. But BPA-based linings are still slathered on the insides of most food and beverage cans, and used to coat water-supply pipes in many countries. The compound is also found in dental sealants and in incubators for premature infants.

BPA-based epoxy linings are widely used because they are strong, flexible and cheap. They tolerate the high temperatures needed to sterilize foods during canning, and do not interact with a huge array of foods and beverages, according to the North American Metal Packaging Alliance in Washington DC. The alliance estimates that 95% of all aluminium and steel can coatings are epoxy-type resins: more than 99.9% of these contain BPA.

New options are beginning to surface. BPS was first made in 1869 as a dye. But because it was introduced into consumer goods only recently — into cash-register receipts in 2006, for example — few researchers have studied its toxicity. “The main question, to which we have no answer, is: 'is BPS as toxic as BPA?'” says René Habert, an endocrinologist at Paris Diderot University.

The similarity of BPS's structure to that of BPA is enough to raise suspicions that it may mimic oestrogens, says Cheryl Watson, a biochemist at the University of Texas Medical Branch in Galveston. When combined with levels of oestradiol found in adult women, BPS seemed to over-stimulate the pathway, shutting it down and causing cell suicide. The results, says Watson, were typical of those expected of an oestrogen mimic: inappropriate activation of oestrogen responses, disruption of normal oestrogen-response pathways, and eventual cell death. 

Some manufacturers have left the bisphenol family in search of a replacement. In 2007, the Eastman Chemical Company launched Tritan — a new heat-resistant clear plastic — for infant-care products such as baby bottles. This BPA-free plastic has since replaced the old BPA-containing polycarbonate in many water bottles, food containers and children's cups. 

In 2011, George Bittner, a neurobiologist at the University of Texas at Austin and the chief executive of Austin-based chemical-testing company CertiChem, reported that 92% of 102 commercially available plastic products leached chemicals with oestrogenic activity7. This included plastics advertised as BPA-free. The reason, Bittner says, is that additives in plastics — such as stabilizers and lubricants — can also bind to oestrogen receptors, as can some of the plastic monomers themselves. Tritan resins produced by Eastman were among the polymers that showed oestrogenic activity in Bittner's assays. 

In 2012, the world produced some 280 million tonnes of plastic. According to a model based on the United Nations' Globally Harmonized System of Classification and Labelling of Chemicals, more than 50% of these plastics contain ingredients that can be hazardous (see Nature 494169171; 2013). Some are carcinogenic; others are oestrogenic.

It is not yet clear how many of these chemicals are dangerous at the concentrations found in the plastics. But mixed together, the chemicals could have synergistic effects

Ideally, says Watson, the next generation of chemicals would be tested for effects on oestrogen signalling before widespread deployment in food containers.

From Mother Jones:

The Scary New Evidence on BPA-Free Plastics

An excellent reason to listen to your mother and eat your vegetables. From the U.S. Department of Health and Human Services site healthfinder.gov:

Vegetables in Childhood May Benefit Breast Health

Girls who ate the most fruits and vegetables rich in carotenoids were less likely to get benign breast disease, a new study suggests.

Carotenoids are a group of pigments that typically produce an orange, red or dark green color. They are believed to have antioxidant properties that may guard against disease. Benign breast disease describes a variety of noncancerous conditions of the breast; some forms raise the risk of breast cancer. 

For her study, Boeke and her colleagues looked at food reports from 1996 through 1998 and then evaluated reports in 2005, 2007 and 2010 from girls who got a diagnosis of benign breast disease from a doctor after having a biopsy. In all, Boeke studied nearly 6,600 girls, and 122 reported a diagnosis of benign breast disease.

When she looked at carotenoid intake, she found high intakes were protective. "The odds of benign breast disease in those who consumed the most beta carotene were about half that of those who consumed the least," she said. Girls in the highest intake group ate two to three servings of carotenoid-rich foods weekly, she said.

She did take into account other factors that might affect the risk of benign breast disease, such as alcohol intake, physical activity, family history and body mass index (a measure of body fat using height and weight).

Why might the fruits and vegetables help? It's not known for sure, but Boeke said it may be due partly to their antioxidant properties. Carotenoids absorb harmful substances known as free radicals which can harm cells.

The study looked only at food intake, not supplements, and Boeke said she would not recommend supplements since other research has found some harmful effects with supplement use. Other foods that are rich in carotenoids include yams, melons, spinach and kale.

The period of time between the start of a girl's period and the first birth is a sensitive one for the breasts, as they are very vulnerable to environmental exposures, according to background information in the study.

Paternal age of 25 to 29 at conception resulted in the lowest risk of adult-onset hormone related cancers in their daughters. From Science Daily:

Father's age at birth may affect daughter's cancer risk

Paternal age and the health effects it has on potential offspring have been the focus of many studies, but few have examined the effect parental age has on the risk of adult-onset hormone-related cancers (breast cancer, ovarian cancer and endometrial cancer).

A team of City of Hope researchers, lead by Yani Lu, Ph.D., explored this relationship and found that a parent’s age at birth, particularly a father’s age, may affect the adult-onset cancer risk for daughters — especially for breast cancer.

“Our findings indicate that parental age, especially paternal age, at conception appears to be associated with a wide range of effects on the health and development of the offspring,” Lu said.

To help determine the effects of parental age on the risk of adult-onset hormone-related cancers, Lu and her colleagues examined a cohort of 133,479 female teachers and administrators from the California Teachers Study. Between 1995 and 2010, 5,359 women were diagnosed with breast cancer, 515 women were diagnosed with ovarian cancer and 1,110 women were diagnosed with endometrial cancer.

While the team of researchers did not find an association for maternal age at birth for any type of cancer, they found that paternal age is linked to an increased adult-onset cancer risk for daughters – and the link was not only to advanced paternal age.

Women born to a father under the age of 20 had a 35 percent greater risk of breast cancer and more than two times greater risk of ovarian cancer, when compared to those born to a father whose age at his daughter’s birth was 25 to 29 years old.

Women born to a father whose age at childbirth was 30 to 34 years had a 25 percent greater risk of endometrial cancer than those born to a father age 25 to 29.

Lu and her team were not surprised to find a relationship between older fathers and an increased risk of hormone-related cancers, especially since there has been increasing evidence suggesting that daughters born to older fathers have increased risk of breast cancer, noted Lu.

“We observed that young paternal age, as well as advanced paternal age, increase the risk of breast cancer,” said Lu. “We also found that young paternal age increases the risk of ovarian cancer.”

This is a depressing research finding, with long-term negative results. From Science Daily:

Four in 10 infants lack strong parental attachments

In a study of 14,000 U.S. children, 40 percent lack strong emotional bonds -- what psychologists call "secure attachment" -- with their parents that are crucial to success later in life, according to a new report. The researchers found that these children are more likely to face educational and behavioral problems.

In a report published by Sutton Trust, a London-based institute that has published more than 140 research papers on education and social mobility, researchers from Princeton University, Columbia University, the London School of Economics and Political Science and the University of Bristol found that infants under the age of three who do not form strong bonds with their mothers or fathers are more likely to be aggressive, defiant and hyperactive as adults. These bonds, or secure attachments, are formed through early parental care, such as picking up a child when he or she cries or holding and reassuring a child.

Written by Moullin, Jane Waldfogel from Columbia University and the London School of Economics and Political Science and Elizabeth Washbrook from the University of Bristol, the report uses data collected by the Early Childhood Longitudinal Study, a nationally representative U.S. study of 14,000 children born in 2001. The researchers also reviewed more than 100 academic studies.

Their analysis shows that about 60 percent of children develop strong attachments to their parents, which are formed through simple actions, such as holding a baby lovingly and responding to the baby's needs. Such actions support children's social and emotional development, which, in turn, strengthens their cognitive development, the researchers write. These children are more likely to be resilient to poverty, family instability, parental stress and depression. Additionally, if boys growing up in poverty have strong parental attachments, they are two and a half times less likely to display behavior problems at school.

The approximately 40 percent who lack secure attachments, on the other hand, are more likely to have poorer language and behavior before entering school. This effect continues throughout the children's lives, and such children are more likely to leave school without further education, employment or training, the researchers write. Among children growing up in poverty, poor parental care and insecure attachment before age four strongly predicted a failure to complete school. Of the 40 percent who lack secure attachments, 25 percent avoid their parents when they are upset (because their parents are ignoring their needs), and 15 percent resist their parents because their parents cause them distress.

Susan Campbell, a professor of psychology at the University of Pittsburgh who studies social and emotional development in young children and infants, said insecure attachments emerge when primary caregivers are not "tuned in" to their infant's social signals, especially their cries of distress during infancy.

"When helpless infants learn early that their cries will be responded to, they also learn that their needs will be met, and they are likely to form a secure attachment to their parents," Campbell said. "However, when caregivers are overwhelmed because of their own difficulties, infants are more likely to learn that the world is not a safe place -- leading them to become needy, frustrated, withdrawn or disorganized."

The report, which is titled "Baby Bonds: Parenting, attachment and a secure base for children," was published March 21 by the Sutton Trust and is available online: http://www.suttontrust.com/our-work/research/item/baby-bonds/.