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More research supports that being exposed to pets during pregnancy or in the first months of life changes the gut bacteria, and in a way that is thought to be beneficial. The researchers found that infants exposed to pets prenatally or after birth (or both) had higher levels of two microbes that are associated with a lower risk of allergies and obesity. The two microbes are Ruminococcus and Oscillospira, but in case you're wondering - they are not (yet) available in probiotics.

And these differences in gut bacteria occurred no matter how the infants were born or fed (C-section, vaginal, breastfed, formula fed), or whether they received antibiotics at birth or not  - it was the pet exposure that was most important. The evidence is building that if one wants to avoid allergies in children - to have them exposed to furry pets in the first  year of life, and according to this study - perhaps before birth also. From Science Daily:

Pet exposure may reduce allergy and obesity

A new University of Alberta study showed that babies from families with pets -- 70 per cent of which were dogs -- showed higher levels of two types of microbes associated with lower risks of allergic disease and obesity.

"There's definitely a critical window of time when gut immunity and microbes co-develop, and when disruptions to the process result in changes to gut immunity," said Anita Kozyrskyj, a U of A pediatric epidemiologist....The latest findings from Kozyrskyj and her team's work on fecal samples collected from infants registered in the Canadian Healthy Infant Longitudinal Development study build on two decades of research that show children who grow up with dogs have lower rates of asthma

Her team of 12, including study co-author and U of A post-doctoral fellow Hein Min Tun, take the science one step closer to understanding the connection by identifying that exposure to pets in the womb or up to three months after birth increases the abundance of two bacteria, Ruminococcus and Oscillospira, which have been linked with reduced childhood allergies and obesity, respectively.

"The abundance of these two bacteria were increased twofold when there was a pet in the house," said Kozyrskyj, adding that the pet exposure was shown to affect the gut microbiome indirectly -- from dog to mother to unborn baby -- during pregnancy as well as during the first three months of the baby's life. In other words, even if the dog had been given away for adoption just before the woman gave birth, the healthy microbiome exchange could still take place.

The study also showed that the immunity-boosting exchange occurred even in three birth scenarios known for reducing immunity, as shown in Kozyrskyj's previous work: C-section versus vaginal delivery, antibiotics during birth and lack of breastfeeding. What's more, Kozyrskyj's study suggested that the presence of pets in the house reduced the likelihood of the transmission of vaginal GBS (group B Strep) during birth, which causes pneumonia in newborns and is prevented by giving mothers antibiotics during delivery. [Original study.]

Another study has linked childhood behavioral problems to pesticide exposure, this time to pyrethroid insecticide exposure. Pyrethroids are synthetic pesticides (insecticides) that are increasingly used for personal use (mosquito repellents and treatments for head lice, scabies), on pets (for fleas), home use (e.g., Raid pesticides), and in agriculture.

Until recently, they have been viewed as "safer" and posing fewer risks to human health than older pesticides, but a growing body of research is finding that pyrethroid pesticides share similar neurocognitive health effects as older pesticides. Neurocognitive refers to the neural processes of the brain and central nervous system involved in cognitive functioning. Pyrethroids get into people various ways: through inhalation, absorbed through the skin, and ingested in food. And yes, they cross the placenta (they have been detected in the placental cord immediately after birth).

In this study, researchers looked at levels of pyrethroid metabolites (the breakdown products from pyrethroids) in the mother's urine during early pregnancy and in the child's urine when the child was 6 years of age. They looked at how social a child is (altruism), whether the child is inhibited and has difficulty sharing problems or asking for help (internalizing behaviors), as well as how defiant or disruptive a child is (externalizing behaviors, which can include hyperactivity and oppositionality).

Pyrethroids (the metabolites) were regularly detected in both mothers and children participating in the study. Internalizing disorders were associated with high levels of one pyrethroid metabolite (cis-DCCA, a breakdown product of permethrin, cypermethrin, and clyfluthrin) in pregnant mothers’ urine. Childhood exposure to pyrethroids (as measured in the child's urine) was linked to externalizing disordersResearchers hypothesized that the behavioral difficulties were due to changes in the child’s brain. The authors stated: “The current study suggests that exposure to certain pyrethroids at the low environmental doses encountered by the general public may be associated with behavioural disorders in children.” "Internalizing behaviors are inhibited and overcontrolled in nature, while children with

Other studies have also found negative health effects on children from pyrethroids -  for example, an association between synthetic pyrethroid exposure and ADHD hyperactivity and impulsivity. Recent research found that living near a farm field where pyrethroids are applied during a mother’s third trimester or just before conception corresponds with a greatly increased risk of having a child with autism spectrum disorder.

What can one do? Main one: try to avoid using and ingesting (in food) synthetic pyrethroids. This means avoid routine "pesticide treatments" of your home and garden, and instead use least-toxic methods to control pests around the home and garden (such as baits for insects, caulk holes, etc.). Try viewing weeds in the lawn as native wildflowers and the flowers as bee habitats (yes, you'll also be saving bees!). Eat as many organic foods (especially fruits and vegetables) as possible - this will lower the amount of pesticides in your body. This is because synthetic pyrethroids are not allowed in organic farming.  The good news is that pyrethroid pesticides leave the body within days, so with some lifestyle changes you can really lower your pesticide levels.

From Medscape:  'Safe' Insecticides Tied to Neurobehavioral Problems in Kids

Prenatal and childhood exposure to pyrethroid insecticides may adversely affect neurobehavioral development in children up to age 6 years, new research shows. A group of French researchers led by Jean-François Viel, MD, PhD, and Prof Andreas G. Franke, MD, both of the University of Mainz, Germany, investigated the associations between exposure to pyrethroid insecticides and behavioral skills in 6-year-olds.

Using a longitudinal design, the researchers assessed pyrethroid exposure in children prenatally and at age 6 years. They found that in 6-year-old children, increased prenatal concentrations of the cis-dimethylcyclopropane carbolic acid metabolite were associated with internalizing difficulties. A positive association was also found between the presence of childhood 3-phenoxybenzoic acid (3-PBA) and externalizing difficulties.

The researchers used a longitudinal design to assess the relationship between prenatal and childhood pyrethroid concentrations, using data from the French PELAGIE mother-child study. That study enrolled 3421 pregnant women from Brittany, France, between 2002 and 2006. Of this cohort, 287 randomly selected mothers agreed to participate in neuropsychological follow-up. Psychologists who were blinded to pyrethroid exposure levels in the study participants conducted neurodevelopmental assessments and maternal interviews to assess the home environment. They also collected children's urine samples as well as dust samples.

A new study has summarized what we know about fungi that live in and on babies - and yes, we all have fungi both on and within us. It's called the mycobiome. In healthy individuals all the microbes (bacteria, viruses, fungi, etc) live in balanced microbial communities, but the communities can become "out of whack" (dysbiosis) for various reasons, and microbes that formerly co-existed peacefully can multiply and become problematic. Or other pathogenic microbes can enter the community, and the person becomes ill.

In healthy adults, approximately 0.1% of the microbes in the adult intestine are fungi, from approximately 60 unique species. Most species live peacefully in the body, and some fungi even have health benefits (e.g., Saccharomyces boulardii prevents gastrointestinal disease). Some fungi that many view as no good and involved with diseases (e.g., Candida and Aspergillus) are also found normally in healthy people. Studies show that normally infants also have fungi. Some fungi that live in the baby's gut (thus detected in fecal samples) are Candida (including C. albicans), Saccharomyces, and Cladosporium. The researchers (from the Univ. of Minnesota) point out that the study of fungi in babies has been neglected and much more research needs to be done.

Whether an infant is born vaginally or through cesarean delivery (C-section) affects the composition of the baby's bacterial communities over the first 6 months of life. And similarly, it looks like when the baby passes through the birth canal, the baby is exposed to the mother's mycobiota (fungi), and then these colonize in the infant's gut. Babies born by C-section have some differences in their fungi, such as being colonized by the mother's skin fungi (such as Malassezia fungi). After birth, a parent kissing and touching the baby (skin to skin contact) also transmits microbes, including fungi, to the baby.

Whether a baby drinks breast milk or formula strongly affects the infant's bacteria within the GI tract. For example, breast-fed infants have more Bifidobacteria and Labctobacilli in their gut compared to formula-fed infants. One study found about 700 species of bacteria in breast milk. Thus, scientists think that human breast milk also influences the infant gut mycobiota (fungi), although this research still needs to be done.

Whether a baby is born prematurely or at term (gestational age) is important. For infants born prematurely, intestinal fungi can cause big problems, such as an overgrowth in the gut. For example, 10% of premature babies get invasive, systemic Candidiasis, and about 20% die. Some factors leading to this are: a naïve immune system, bacterial communities out of whack (dysbiosis) due to antibiotic exposure, and use of parenteral nutrition (because this doesn't contain all the microbes from the mother that are in breast milk). In premature infants, beneficial fungi such as S. boulardii, may help to regulate the growth of opportunistic fungal colonizers such as Candida.

it is clear that whether the baby received antibiotics is important. The bacterial community of infants is altered by exposure to antibiotics in both term and preterm infants. For example, in a lengthy study over the first 3 years of life, infants receiving multiple courses of antibiotics had bacterial community changes following antibiotics and their gut bacterial microbiome became less diverse (fewer species). Although most commonly used antibiotics do not directly act on fungi, anti-bacterial antibiotic exposure is associated with alterations to the mycobiota (fungi) -  such as increased rates of fungal colonization, fungal overgrowth, and changes in the fungal community. For ex., premature infants exposed to cephalosporin antibiotics have an increased risk for invasive Candidiasis (a fungal overgrowth).

Out of whack (dysbiotic) microbial communities, incuding fungi, are found in IBD (intestinal bowel diseases) in children. They have more of some fungi (e.g. Pichia jadinii and Candida parapsilosis) and less of Cladosporium cladosporiodes, and an overall decrease in fungal diversity in the gut, as compared to healthy children.

From BMC Medicine: Infant fungal communities: current knowledge and research opportunities

The microbes colonizing the infant gastrointestinal tract have been implicated in later-life disease states such as allergies and obesity. Recently, the medical research community has begun to realize that very early colonization events may be most impactful on future health, with the presence of key taxa required for proper immune and metabolic development. However, most studies to date have focused on bacterial colonization events and have left out fungi, a clinically important sub-population of the microbiota. A number of recent findings indicate the importance of host-associated fungi (the mycobiota) in adult and infant disease states, including acute infections, allergies, and metabolism, making characterization of early human mycobiota an important frontier of medical research. This review summarizes the current state of knowledge with a focus on factors influencing infant mycobiota development and associations between early fungal exposures and health outcomes. We also propose next steps for infant fungal mycobiome research....

Avoid eating licorice during pregnancy? That licorice is a food to avoid during pregnancy (or only eat in tiny amounts) will be news to many. Most people think of licorice (or liquorice) as a candy, but it can also be used as a herbal medicine that can have negative health effects, especially in large doses (e.g, high blood pressure, loss of potassium). The licorice flavor comes from the root of the plant (licorice root). Licorice contains glycyrrhizin, which is in black licorice candy, and in some chewing gums, ice creams, syrups, soft drinks, supplements, herbal teas, and other products.

In 2016, the government of Finland warned against consuming licorice (including black licorice and salty licorice) during pregnancy. In the United States, the FDA does not warn pregnant women about eating licorice or licorice root. The National Institutes of Health (NIH) recommends that pregnant women avoid consuming large amounts of licorice root in food or taking it as a supplement. But how about small amounts of licorice? And what are possible effects during pregnancy?

A recent study in Finland compared children (average age of 12 1/2 years) whose mothers had either consumed little to no licorice during pregnancy or had consumed large amounts of licorice (high glycyrrhizin levels were calculated as more than 500 milligrams per week). Note that 500 mg glycyrrhizin is equal to 250 grams or 8.8 oz licorice. The researchers found that children whose mothers ate large amounts of licorice during pregnancy  were about 7 points lower on IQ tests, had poorer memory, and had higher rates of attention deficit/hyperactivity disorder problems than those whose mothers had eaten little or no licorice during pregnancy. High-consumption group girls had earlier and more advanced puberty, and were taller and heavier than those in the low-licorice group.

The researchers wrote that glycyrrhizin results in "glucocorticoid overexposure", which may affect the developing fetus, and the effects persist into early adolescence. The study researchers concluded that pregnant women should be informed that consumption of licorice and other food products containing glycyrrhizin may be associated with harm to their developing baby. A little licorice candy here and there during pregnancy seems to be OK (so don't panic!), but licorice or licorice root is not something that should be eaten or drunk (e.g.,in a tea) regularly. From Science Daily:

Pregnant women should avoid liquorice

A new Finnish study supports food recommendations for families with children in that women should avoid consuming large amounts of liquorice during pregnancy. The limit for safe consumption is not known. In the study, youths that were exposed to large amounts of liquorice in the womb performed less well than others in cognitive reasoning tests carried out by a psychologist. The difference was equivalent to approximately seven IQ points. Those exposed to liquorice also performed less well in tasks measuring memory capacity, and according to parental estimates, they had more ADHD-type problems than others. With girls, puberty had started earlier and advanced further.

The Glaku study carried out by the University of Helsinki, the National Institute for Health and Welfare and the Helsinki and Uusimaa hospital districts compared 378 youths of about 13 years whose mothers had consumed "large amounts" or "little/no" liquorice during pregnancy. In this study a large amount was defined as over 500 mg and little/no as less than 249 mg glycyrrhizin per week. These cutoffs are not based on health effects. 500 mg glycyrrhizin corresponds on average to 250 g liquorice.

Researchers suggest that pregnant women and women planning pregnancy should be informed of the harmful effects that products containing glycyrrhizin -- such as liquorice and salty liquorice -- may have on the fetus. In Finland, this is already reality. In January 2016, the National Institute for Health and Welfare published food recommendations for families with children, in which liquorice was placed in the 'not recommended' category for pregnant women. According to the recommendations, occasional consumption of small amounts such as a portion of liquorice ice cream or a few liquorice sweets is not dangerous.

As a result of animal experiments, the biological mechanism of the effects of liquorice is well known. Glycyrrhizin intensifies the effects of stress hormone cortisol by inhibiting the enzyme that inactivates cortisol. While cortisol is essential to the development of a fetus, it is detrimental in large amounts. It has long been known that glycyrrhizin causes higher blood pressure and shorter pregnancies in humans, but such long-lasting effects on the fetus have not been proven before. [Original study.]

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Another study is adding to the evidence that food packaging  is frequently coated  with harmful chemicals - called perfluorinated chemicals or PFCs. The chemicals are used because they resist grease and stains, but unfortunately they then leach into the food, and when people eat the food - it gets into them. The evidence is also growing that these chemicals have all sorts of harmful health effects, including endocrine disruption (they are hormone disruptors) - even in low doses. They are linked to kidney and testicular cancer, high blood cholesterol levels, thyroid problems, development and immune system problems, low birth weights, and decreased sperm quality. (See earlier post) The list keeps growing each year.

Researchers tested about 400 pieces of food packaging from 27 fast food chains,  including McDonald’s, Burger King, Taco Bell, Chick-Fil-A, Quiznos, Starbucks, and Dunkin’ Donuts (see how they scored). Overall, about 33 percent of the packages contained fluorine (a chemical not found in paper, but is an indicator of perfluorinated chemicals present to make the packaging grease and stain resistant). What is even more disturbing is that when the researchers more closely examined 20 samples to find out exactly what fluorinated compounds they contained - they found that 6 of the more rigorously tested packages contained PFOA (which was used in Teflon). PFOA was phased out for use in the USA years ago due to it being so long-lasting in the environment and its serious health effects, but other countries still produce it. Unfortunately, even the replacement chemicals  seem to be similarly harmful (not surprising because of the chemical similarities), and they also persist in the environment.

It should be pointed out that perfluorinated chemicals are also used in products such as stain and water resistant coatings on clothing, upholstery, carpeting and floor waxes. They are in non-stick coatings in pots and pans. The chemicals leach or migrate out of products and degrade very slowly — thus showing up in air, household dust, water, dirt, wildlife, and people. Yes, studies show that almost everyone in the U.S. has these chemicals in their blood, and unfortunately some of them can stay in the body for years. PFCs pass from mothers to their babies during pregnancy, and in breast milk after birth. Exposure to perfluorinated chemicals from fast food packaging is of big concern for children, because one-third of U.S. children consume fast food daily, and children may be especially susceptible to the adverse health effects.

Yes, we are surrounded by a sea of harmful chemicals that are tough to avoid, but we should at least try to minimize our exposure. Fast food restaurants should be encouraged to use nontoxic alternatives (e.g., aluminum foil or wax paper) - after all, the study showed that there is packaging out there without these chemicals.

What can we do to avoid PFCs? 1) Try to avoid or eat less fast food and food that comes in "grease-proof" containers. 2) Don't use non-stick pots and pans - use stainless steel instead. 3) Try to avoid clothing, upholstered furniture, and carpets with stain and water-resistant coatings. 4) Don't use microwave popcorn bags, and try to avoid microwaving foods in their packaging - use a glass dish instead. 5) Don't use dental floss such as Oral-B Glide dental floss (uses PFC), and use unwaxed or natural wax floss instead. 6) Avoid personal care products that contain ingredients that include the words “fluoro” or “perfluoro". *Please check out the Environmental Working Group site for more information (here and here).

From Science Daily: Extensive use of fluorinated chemicals in fast food wrappers: Chemicals can leach into food

Americans may be consuming fast food wrapped in paper treated with perfluorinated chemicals (PFCs) -- the same chemicals used in stain-resistant products, firefighting materials and nonstick cookware, according to a new study published in the journal Environmental Science & Technology.

Researchers tested more than 400 samples of packaging materials, including hamburger and sandwich wrappers, pastry bags, beverage cups and French fry containers, and found evidence of fluorinated compounds called per- and polyfluoroalkyl substances (PFASs). Of the materials tested, these chemicals were found in 56 percent of dessert and bread wrappers, 38 percent of sandwich and burger wrappers and 20 percent of paperboard.

Previous studies have shown that these PFASs can migrate, contaminating the food and, when consumed, accumulating in the body....Previous studies have linked PFASs to kidney and testicular cancers, thyroid disease, low birth weight and immunotoxicity in children, among other health issues. The chemicals have an especially long half-life and take many years before just 50 percent of the intake leaves the human body. The results are concerning when considering the role of fast food in the American diet. The National Center for Health Statistics reported one-third of U.S. children consume fast food daily.

Samples were collected from a total of 27 fast food restaurant chains including McDonald's, Burger King, Chipotle, Starbucks, Jimmy Johns, Panera and Chick-Fil-A, in and around Boston, San Francisco, Seattle, Washington, D.C., and Grand Rapids, Michigan. The study did not include takeout containers, such as Chinese food boxes or pizza boxes. [Original study]

Both males and females should consider trying to lower their exposure to endocrine disrupting chemicals (hormone disrupting chemicals) when contemplating pregnancy. These chemicals are found in many personal care, food packaging, and plastic products. They can interfere with natural hormone function and are linked to a wide assortment of health problems. Evidence (like this study) is mounting that higher levels of endocrine disruptors in the body have a negative effect on the developing embryo. So men - an important time to try to lower your exposure to endocrine disruptors is the 3 months preconception (it takes about 3 months for sperm to mature), and for women it's the entire pregnancy period (from conception to birth). You can't totally avoid endocrine disrupting chemicals (they're detected in almost all of us), but you can lower your exposure.

What to avoid and what to do? Read the ingredient lists of all personal care products and try to avoid those with phthalates, parabens, triclosan, bisphenol-A (BPA), BPS, triclocarbon, and oxybenzone (BP-3). Try to buy "unscented" or "fragrance-free" products. Canned foods are considered one of the most significant routes of human exposure to bisphenol A (BPA), so limit canned foods. Note that "BPA-free" cans and plastic containers also contain endocrine disruptors. Another way to lower exposure to endocrine disruptors is to buy and store food not in plastic containers, but in glass containers or stainless steel. Don't microwave food in any sort of plastic containers. Avoid products with fragrances in them, including air fresheners and dryer sheets. Avoid flexible vinyl (e.g. shower curtains). [For all posts on endocrine disruptors, and an article from National Institutes of Health. Also check ewg.org for lists of products]. From Environmental Health News:

Are plastic chemicals in dads hurting embryos?

Turns out, moms, it's not just about you staying off alcohol and avoiding potentially harmful chemicals while pregnant or trying to become so. Your partners' exposure to plastics and packaging could play an important role in your ability to conceive a child. A father’s exposure to chemicals commonly found in plastics, personal care products and food packaging might decrease the quality of embryos produced by their sperm, according to a new study out of Massachusetts.

The study, published today in the journal Human Reproduction, is the first to examine dads’ exposure to phthalates and embryo quality through five days of in vitro fertilization (IVF). The lower quality embryos had fewer signs of the type of progress that leads to a fetus. The findings suggest men’s exposure to the chemicals—used in vinyl products, food packaging, fragrances and in other plastics to make them pliable—might hamper the development of their unbornEmbryos are the result of a fertilized egg in a woman and are the precursor to the fetus. About 12 weeks into pregnancies, the unborn is considered a fetus.

Most people have phthalates in their bodies and the compounds disrupt the endocrine system—interfering with hormones that are crucial for reproduction.While the study doesn’t prove phthalates in men lead to poor quality embryos, it adds to mounting evidence that the ubiquitous chemicals may impact pregnanciesSperm mature over 72 days on average, almost three months,” said senior author of the study, Richard Pilsner, an epidemiologist and assistant professor at the University of Massachusetts Amherst. “During that time, we may tell men to maybe try to avoid phthalates. There’s no way to totally escape exposure but you could minimize it.

Led by Pilsner, researchers collected 761 immature eggs from 50 couples undergoing IVF at the Baystate Medical Center in Springfield, Mass., and checked their progression to embryos. They tested embryos at three days and five days after the eggs were fertilized, and collected urine samples from the couples on the same day as the semen sample and egg retrieval to test for phthalate metabolites, substances formed after the body processes phthalates. At day five, high exposure to phthalates in men was linked to fewer—or no—signs of the type of development that eventually leads to a fetus and placenta compared to men with lower exposure.

Phthalate exposure for fetuses has been linked to genital defects, lower IQs and miscarriages but it’s not clear what impacts this poor embryo quality could mean for the unborn. Russ Hauser, a professor of reproductive physiology at Harvard University, said in an email that the impacts might range from pregnancy loss to effects on children's health later in their life.

Shanna Swan, a professor of reproductive science at Mount Sinai Hospital in New York who was not involved in the study, said the study is limited in that it is small, and not representative of the general population because it only included couples undergoing IVF. They also didn’t see any association with the women’s exposure and decreased embryo quality. But this isn’t the first study to report a male-only effect. Higher phthalates in father’s urine was associated with an increased time for couples to conceive, according to a 2014 study. Swan said the current study was strengthened in that it is “remarkably consistent” with the 2014 study. Some phthalate metabolites linked to impacts in both studies are known to target male reproductive hormones, she said.

I've been asked whether vegan diets are safe during pregnancy. And I've always said that I don't know, but that avoiding all meat, fish, eggs, and dairy concerns me. Vegan diets are diets without meat, fish, dairy, honey, and eggs (no animal derived food), but while vegetarian diets also avoid meat, they do include eggs, honey, milk, and dairy products. Thus it is very important that anyone following a vegan diet plan meals carefully to get all the necessary nutrients. For example, soda and french fries are vegan, but are not good nutritionally.

There are a number of nutrients that probably need to be supplemented in vegan diets during pregnancy, especially B-12, iron, zinc, iodine (can get by using iodized salt), and omega-3s, and that's not even discussing micronutrients. So it was good to see this article by Dr. Drew Ramsey (Columbia University, NY) raising those same concerns about nutrient deficiencies during pregnancy, and pointing out that very few studies have looked at vegetarian and vegan diets in pregnancy - that the evidence is "scant". This topic is so controversial that as of today there were 85 comments by health professionals after the following Medscape article - both strongly pro and con, and studies given that show that vegans tend to have lower levels of a number of nutrients measured (zinc, iron, omega-3s, etc).

There are also reports of babies exclusively breast-fed by vegan mothers (here and here) who did not take vitamin supplements that developed nutritional deficiencies (especially B-12, vitamin K, and vitamin D). This is because what a mother eats is what the baby gets during pregnancy and breast-feeding.

On the other hand, the Academy of Nutrition and Dietetics came out with a position statement in 2016 stating that "appropriately planned vegetarian, including vegan, diets are healthful, nutritionally adequate, and may provide health benefits for the prevention and treatment of certain diseases. These diets are appropriate for all stages of the life cycle, including pregnancy, lactation, infancy, childhood, adolescence, older adulthood, and for athletes". But that article (in the Journal of Academy of Nutrition and Dietetics) then goes on in depth about several nutrients that can be lower or deficient in vegan diets unless supplements are given (B-12, iodine, etc). From Medscape;

Are Vegan and Vegetarian Diets Safe During Pregnancy?

Are vegan and vegetarian diets safe during pregnancy?....Vegan and vegetarian diets are plant-based diets....Plants, in general, are a great choice, especially colorful plants, because they tend to be more nutrient-dense. Plant-based diets have been linked to a number of health benefits, such as lower body mass index and lower rates of obesity and diabetes, as well as conferring some benefits. Certainly, vegan and vegetarian diets have higher amounts of certain nutrients like magnesium, folate, and fiber, all of which are generally consumed in very low quantities in Western diets.

Focusing on pregnancy, there are two important papers to note. The first, which got me very interested in this issue, was a series of pooled case reports by Drs Dror and Allen in 2008.[1] They looked at 30 cases of severe vitamin B12 deficiency during pregnancy in vegan women with pernicious anemia. Among the 30 vegan women who had B12 deficiency during pregnancy, about 60% of their offspring had severe developmental delays and 37% had cerebral atrophy.... The clinical importance of this is to partner with our patients who are eating plant-based diets and ensure that they have adequate levels of vitamin B12, as well as iron, zinc, and long-chain omega-3 fats during pregnancy.

The second article to take a peek at is from the British Journal of Obstetrics and Gynaecology in 2015.[2] This was a systematic review that looked at all of the literature after screening out the papers. The authors found about 13 papers focusing on maternal and infant outcomes, and about nine of those looked at nutrient deficiency. The main headline of this review is that there are no randomized clinical trials of vegan or vegetarian diets in pregnancy. It is very hard to make a clear clinical recommendation. The epidemiologic data were heterogeneous. As the researchers called it, it was "scant." That is certainly true. Overall, there were no clear associations with bad outcomes. There was some increased risk for hypospadias in one of the larger trials that looked at vegan and vegetarian diets during pregnancy.

The main concern is that vegan and vegetarian diets put patients at risk for a number of nutrient deficiencies—vitamin B12 in vegan diets (and even for vegetarians), iron, zinc, and the long-chain omega-3 fats. Just a quick moment on the long-chain omega-3 fats: Dietarily, these only come from fatty fish and seafood. They are bioconcentrated. They start in algae, but they get bioconcentrated in our food supply via seafood. It is very hard to get those during pregnancy. Certainly, a lot of healthy babies have been born to vegetarian and vegan women. You can supplement, but given the benefits we see with omega-3 fats in patients with things like mood disorders or a history of psychotic disorders, I think it is important to consider the long-chain omega-3 fats. If someone is not going to get those in their diet but has a history, risk, or propensity toward mood disorders, think about supplementation. 

Excerpts from the review study (mentioned above) in BJOG: Vegan-vegetarian diets in pregnancy: danger or panacea? A systematic narrative review.

To review the literature on vegan-vegetarian diets and pregnancy outcomes [in healthy pregnant women]....None of the studies reported an increase in severe adverse outcomes or in major malformations, except one report of increased hypospadias in infants of vegetarian mothers. Five studies reported vegetarian mothers had lower birthweight babies, yet two studies reported higher birthweights. The duration of pregnancy was available in six studies and was similar between vegan-vegetarians and omnivores. The nine heterogeneous studies on microelements and vitamins suggest vegan-vegetarian women may be at risk of vitamin B12 and iron deficiencies.

CONCLUSIONS: The evidence on vegan-vegetarian diets in pregnancy is heterogeneous and scant. The lack of randomised studies prevents us from distinguishing the effects of diet from confounding factors. Within these limits, vegan-vegetarian diets may be considered safe in pregnancy, provided that attention is paid to vitamin and trace element requirements.

A big concern nowadays is why some children develop autism, specifically autism spectrum disorder (ASD). Autism spectrum disorder is considered a life-long neurodevelopmental disorder that is thought to affect 1 out of 68 American children. While the causes of ASD are unknown in most cases, some studies report an association (higher risk) between a pregnant woman's infections and fever during pregnancy and risk of ASD in the baby, while other studies don't find such an association. Some studies also looked at the timing of infections during pregnancy, but again results have been mixed. A viral infection during the first trimester is associated with increased risk in some studies, while other studies report an increased risk with a second- or third-trimester bacterial infection.  So it has been unclear whether a flu (influenza) infection or flu vaccination during pregnancy is linked to autism spectrum disorder or not. Is there a link or not?

Why are pregnant women encouraged to get a flu shot (flu vaccine)? This is because pregnant women have an increased risk of complications from the flu infection. Studies also show that getting a flu vaccine during pregnancy reduces the risk of a preterm birth, a small-for gestational-age child, and a low-birth-weight child, and prevents influenza infection in newborns for up to 6 months.

The researchers of a large study done in California found no association between autism spectrum disorder (ASD) risk and flu (influenza) infection during pregnancy or flu (influenza) vaccination during the second to third trimester of pregnancy. However, there was a suggestion of increased ASD risk among children whose mothers received flu vaccinations during the first trimester (though the researchers say the association was perhaps due to "chance". Bottom line: the study results were reassuring for pregnant women, but if one wanted to be ultra-cautious, then delay getting a flu shot until the second trimester of pregnancy. From Science Daily:

No association between mother's flu in pregnancy, increased child autism risk

A study of more than 196,000 children found no association between a mother having an influenza infection anytime during pregnancy and an increased risk of autism spectrum disorders (ASDs) in children, according to a new study published online by JAMA Pediatrics. The study by Ousseny Zerbo, Ph.D., of Kaiser Permanente Northern California, Oakland, and coauthors included 196,929 children born in the health system from 2000 through 2010 at a gestational age of at least 24 weeks.

Within the group, there were 1,400 mothers (0.7 percent) diagnosed with influenza and 45,231 mothers (23 percent) who received an influenza vaccination during pregnancy. There were 3,101 children (1.6 percent) diagnosed with ASD. The authors report no association between increased risk of ASD and influenza vaccination during the second and third trimesters of pregnancy. There was a suggestion of increased risk of ASD with maternal vaccination in the first trimester but the authors explain the finding was likely due to chance because it was not statistically significant after adjusting for multiple comparisons. The study cannot establish causality and has several limitations, including ASD status determined by diagnoses on medical records and not validated by standardized clinical assessment for all cases. [Original study.]

An important study was recently published that documents that when pregnant women are exposed to potentially harmful chemicals in the environment around them (environmental pollutants), many of these chemicals also get transferred to the fetus. Many of the 59 chemicals looked for were detected in the newborn babies' umbilical cords (thus the chemicals had crossed the placenta to the fetus during the pregnancy). Some chemicals were measured in higher levels in the umbilical cord than in the mother (as measured in her blood), while only cadmium appeared in mothers, but not in the umbilical cord (thus there was some protection for the fetus from that particular chemical).

This study did not look at the effects on the fetus and newborn from exposure to all these toxic chemicals - it just found that out of 59 chemicals tested for, the median number was 25 in maternal blood and 17 in umbilical cord blood. Eight of the 59 chemicals analyzed were detected in more than 90 percent of both the maternal and cord blood samples - and these included lead and mercury.

The researchers pointed out that no human studies have examined the developmental and reproductive health effects on the fetus and baby from being exposed to multiple chemicals simultaneously during pregnancy - which of course can have bigger risks and negative effects than being exposed to only one chemical at a time. Other studies have already shown that there are negative health effects (adverse neurodevelopmental effects) from a number of these chemicals, such as PCBs, PBDEs, Pb (lead) and Hg (mercury). Bottom line: No one really knows what these mixtures of chemicals do to the developing baby, but it is known that these chemicals have potential health risks. From Futurity:

Mom’s exposure to toxic chemicals shows up in newborn

Low-income and Latina pregnant women in a recent study had widespread exposure to environmental pollutants. In addition, many of the toxins showed up at even higher levels in their newborns. The study is the first in the United States to measure exposure to 59 toxic chemicals in pregnant women and their newborns.

“Pregnant women in the US are exposed to many harmful industrial chemicals that have been linked to premature birth, low birth weight, and birth defects, but estimates of how efficiently pollutants are transferred from mother to fetus have varied widely,” says Tracey Woodruff, professor of obstetrics, gynecology, and reproductive sciences and the Philip R. Lee Institute for Health Policy Studies at the University of California, San Francisco. “Our findings have found that many chemicals do indeed accumulate in the fetal environment and are absorbed at greater levels by fetuses than by the pregnant women themselves. This may have significant consequences for the growing fetus, since many of these chemicals are known to affect development.”

Researchers measured polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), perfluorinated compounds (PFCs), mercury, and lead, among other chemicals. These industrial pollutants are common in the environment, and in previous studies many have been detected in greater than 99 percent of US pregnant women, according to National Health and Nutrition Examination Survey (NHANES) data.

“Contrary to previous research, we found evidence that several PCBs and OCPs were often higher in umbilical cord samples than in maternal blood samples,” says Rachel Morello-Frosch,  professor of environmental science, policy and management at the University of California, Berkeley. The study also found that concentrations of mercury and certain PBDEs were often higher in umbilical cord samples than in maternal samples, and for most PFCs and lead, cord blood concentrations were generally equal to or lower than maternal concentrations, which is consistent with previous research.

Almost 80 percent of the chemicals detected in maternal blood samples were also detected in the umbilical cord blood samples, indicating that they passed through the placenta and entered the fetal environment, where they can pose a health risk to the developing baby. For those chemicals detected in at least 20 paired maternal and umbilical cord samples, 77 percent had significant correlations between maternal and umbilical cord concentrations.

The women in the study were participating in the Chemicals in Our Bodies Study, also referred to as the Maternal and Infant Environmental Exposure Project. Of the women participating in the current study, 95 percent had a combined annual household income of less than $40,000, two-thirds were Latina, and a third were born in Mexico, where they may have had less exposure to environmental toxics like the PBDEs found in flame retardants that have been widely used in the US. This demographic is often not well-represented in larger biomonitoring studies, such as NHANES, that form the basis of most of what is known about pregnant women’s exposure to environmental toxics nationally.

The study also provides a first indication of how several different classes of environmental chemicals found in a pregnant woman’s blood are also present in the newborn....From 2010 to 2011, researchers collected maternal blood samples from 77 pregnant women at Zuckerberg San Francisco General. Once they delivered their babies, researchers collected umbilical cord blood samples from 65 of these women. Of those samples tested for all 59 chemicals, the median number was 25 in maternal blood and 17 in umbilical cord blood. Eight of the 59 chemicals analyzed were detected in more than 90 percent of both the maternal and cord blood samples. 

More bad news about BPA (bisphenol A) - an endocrine disrupter linked to a number of health problems, including reproductive disorders (here, here, and here). A new study has lent support for a  link between bisphenol A (BPA) exposure during pregnancy and later breast cancer. BPA can cross the placenta in the womb, and so expose the fetus, it has been found in placental tissue, and newborns can be exposed through breastfeeding. BPA is found in the urine of about 95% of the U.S. population.

It's hard to avoid BPA because it's found in so many products, but a person can lower exposure to it by avoiding canned products (it's in the can linings), as well as plastic bottles and containers, microwaving or heating food in plastic containers, and fast food (it's in the packaging and leaches into the food) . Glass and stainless steel is OK for storing food. By the way, BPA substitutes such as BPS  and BPSIP have the same negative health effects (because they're chemically similar) - so also avoid "BPA-free" products. From Endocrine News;

A Pervasive Threat: The Danger of in utero BPA Exposure

A new study presented at ENDO [Endocrine Society] 2016 revealed a possible link between bisphenol A exposure in utero to breast cancer later in life. In the process, the researchers created a new bioassay that can test chemicals much faster than typical animal studies. Almost every single person alive today has detectable amounts of endocrine-disrupting chemicals (EDCs) in his or her body, according to the 2015 joint Endocrine Society/IPEN publication Introduction to Endocrine Disrupting Chemicals (EDCs): A Guide for Public Interest Organizations and Policy-Makers.

These EDCs — phthalates (plasticizers), bisphenol A (BPA), polychlorinated biphenyls (PCBs), and others, in their bodies — are hormone-like industrial chemicals that did not even exist 100 or so years ago. Studies on human populations consistently demonstrate associations between the presence of certain chemicals and higher risks of endocrine disorders such as impaired fertility, diabetes, obesity, cardiovascular disorders, and cancer.

The xenoestrogen BPA is especially prevalent as a component used in rigid plastic products such as compact discs, food and beverage containers, food and formula can linings, and glossy paper receipts. In the case of food containers, when they are heated or scratched, the BPA can seep out into the food and then be ingested. BPA also escapes from water pipes, dental materials, cosmetics, and household products among others and is released into the environment or directly consumed. According to research, such exposures help account for why BPA has been found in the urine of a representative sample of 95% of the U.S. population.

Notably, BPA can cross the placenta in the womb, indirectly exposing the fetus — it has been found in both maternal and fetal serum as well as neonatal placental tissue. Newborns can also be directly exposed through breastfeeding.

The results of a study presented at ENDO 2016 provide compelling support for the idea that fetal exposure to BPA might increase risk for development of breast cancer in adulthood; in fact, it may explain why overall incidence increased in the 20th century. Lucia Speroni, PhD, a research associate and member of the Soto-Sonnenschein lab at Tufts University School of Medicine in Boston and the study’s lead investigator, reports, “We found that BPA acts directly on the mammary gland and that this effect is dose dependent: A low dose significantly increased ductal growth, whereas a high dose decreased it.”

“Because these effects are similar to those found when exposing the fetus through its mother, our experiment suggests that BPA acts directly on the fetal mammary gland, causing changes to the tissue that have been associated with a higher predisposition to breast cancer later in life,” Speroni explains. In replicating the process of mammary gland development in vitro, this method additionally allows for live observation throughout the whole process.....The lab team had previously shown that the most harmful time for exposure to BPA is during fetal development by causing alterations in the developing mammary gland.