The First Forty Days
If a woman gets the flu during her first trimester, her child is seven times as likely to develop schizophrenia as a teenager or young adult. It may not be the flu itself that causes the malfunction, but rather an immunological reaction. Cytokines—proteins the mother's body produces in response to the flu—get transmitted to the fetus and harm its brain.
What is really intriguing is that mice that were given a specific cytokine, interleukin-6, gave birth to offspring who not only displayed schizophrenic-like behaviors but also behaviors analogous to those seen in autistic humans.
A 2008 study suggests that 12 to 15 percent of autism cases may occur because maternal autoantibodies—antibodies that a person makes against something in themselves—interfere with proteins in the fetal brain. After identifying unusual antibodies in women who had more than one autistic child, researchers injected the antibodies into four pregnant monkeys. They also gave antibodies taken from women with healthy children to another four pregnant monkeys. The offspring of the monkey mothers who received the regular antibodies were fine, but all four of those whose mothers got the unusual autoantibodies spontaneously developed bizarre tics, such as pacing and doing repeated backflips. "Repetition of motor behaviors is one of the three cardinal features of autism," says David Amaral, a neuroscientist at the M.I.N.D. Institute at the University of California, Davis, who headed the study. Scientists don't know under which conditions these autoantibodies form, nor why they do so.
They do know that a critical window for development is 20 to 40 days after fertilization. During that time, fetuses that eventually develop autism or schizophrenia often begin to display shared physical characteristics, such as protruding ears and unusual toes.
A groundbreaking idea could hold the answer to the puzzle of why some children are autistic while others become schizophrenic. Researchers Bernard Crespi and Christopher Badcock argue that a struggle between genes from Dad's sperm and Mom's eggs results in different expressions of the same genes. When a genetic region that plays a role in brain development is disrupted, the theory says, if the genes inherited from the father dominate, the disruption gives rise to autism, whereas if the genes inherited from the mother dominate, the interference will result in schizophrenia.
Quality of (In Utero) Life Issues
A fetus's only source of sustenance is the food and oxygen its mother takes in, and its access to those supplies can be precarious. The mom's meals nourish her first, then travel a winding path—through temporarily expanded uterine arteries to the greedy placenta, and finally along the rope-like umbilical cord.
If a mother eats a low-calorie or low-protein diet, or one deficient in essential fats or critical nutrients, such as folic acid, vitamin D, or iron, a fetus may lack the raw materials it needs to properly build its brain and other organs. (Iron-deficient infants are shyer, fussier, and less sociable.) Children born to women who are pregnant during a famine, for example, are more susceptible to heart disease and depression when they grow up. Starved fetuses build smaller organs with fewer blood vessels, which can lead to high blood pressure later on. Animal research suggests that not eating enough in the first days after conception can increase the potential for cardiovascular disease and diabetes, which is why women should eat well while trying to get pregnant.
But eating too much is also risky. When women gain more than the recommended weight during pregnancy (25 to 35 pounds for healthy women), their kids are 48 percent more likely to be overweight at the age of seven. A high-fat diet during pregnancy reshapes rat offspring's brains, making them crave fatty foods and putting them at risk for lifelong obesity.
The negative effects of drinking while pregnant are well-known: Alcohol can damage key areas of the fetal brain, including the prefrontal cortex—the region responsible for planning, decision-making, and emotional restraint. What's new and disturbing is research showing that imbibing just a couple of drinks a day during the first 50 days after conception, when a woman may not yet know she is pregnant, creates the strongest effects.
Chemicals that lurk invisibly in our clothes and furniture, in the food we eat, and in the air we breathe dominate today's world. Some, like bisphenol A, a compound in some plastic water and baby bottles, resemble hormones such as estrogen that are produced by our own bodies, which makes them potentially harmful even at very low levels because the body is primed to respond to them. There is concern that the increase in abnormalities of newborn boys' reproductive organs—the rate of hypospadias, a birth defect of the urethra, doubled in the U.S. between 1970 and 1993—results from maternal exposure to such chemicals.
Faith, Love, and Compensation
My sons were born free of Listeria, and in fact were healthy in every way. But I now realize that there could be hidden problems. Twins have a harder time in utero because a mother can supply only so much food and oxygen, and they must share it. On top of that, this was my first pregnancy and I was over 35—factors that limit the stretchiness of the blood vessels that shuttle oxygen and nutrients to the uterus. Let's just say my fetuses were getting their supplies through a coffee stirrer instead of a straw.
And yet I remind myself: Birth is a beginning, not an ending. Nurturing and mental stimulation can reverse the effects of a compromised pregnancy. Monk and colleagues found that 4-month-old infants had high levels of stress hormones in their saliva when their mothers were anxious or depressed before the birth and unresponsive afterward. But when moms were attuned to their babies, the infants' cortisol levels were normal, no matter what the pregnancy was like.
If children learn good exercise and eating habits, they are unlikely to become obese or get diabetes. If their parents and other caregivers engage and nurture them, it is less likely they will develop learning or conduct disorders. "You can look at it as though the system has been primed," says Marta Weinstock-Rosin, a psychopharmacologist at Hebrew University in Jerusalem. "But if nothing else bad happens and everything is calm, it may well be all right."
And with an enriched upbringing, a compromised prenatal environment might even be turned to advantage. When brain development has been altered because a pregnant woman was highly anxious, drank martinis, or ate too much mercury-tainted fish, the resulting baby may be high-strung and hard to soothe. But the same sensitivity that leads to moodiness can also confer empathy and awareness. "You might just be more able to take in what's around you and actually do even better than average," Monk says.
Still, there's no getting around the fact that a mother's experiences profoundly shape her developing baby. Now that I know this, would I live my pregnancy differently? Absolutely. I would have eaten organic as much as possible to reduce my fetuses' exposure to toxins. To ensure that they had all the essential building blocks to grow healthy brain tissue, I would have poured flaxseed oil over my cereal and served up kale and broccoli almost every night. I would have begun taking prenatal vitamins and iron before getting pregnant. And imagining those little guys depending on me for all their oxygen, I would have thrown myself into yoga and spent 10 minutes every morning and evening taking deep breaths.
But I also remind myself of what I did right—a fair amount, judging from the mischievous, affectionate 2-year-olds my boys have become. "To have a baby is a huge affirmation and commitment to life and love," Monk says. Besides doing their best to stay healthy, mothers have no choice but to take a big leap of faith. —Emily Laber-Warren
Timed Health Tips
Expecting mothers are bombarded with guidelines, but some do's and don'ts are particularly important during specific windows in a fetus's development. Here are a few time-sensitive hints for optimizing the prenatal environment.
Pre-Conception
•Get regular exercise. The better your cardiovascular health going into pregnancy, the more oxygen and nutrients you'll pipe to the developing baby.
•Drop that glass of wine with dinner. The offspring of pregnant monkeys who sipped just two drinks a day have subtle learning and emotional problems. The alcohol was most damaging during the first several weeks of pregnancy, when you may not yet realize you're pregnant.
•Get a flu shot to reduce the chance of getting the virus. Make sure you've been vaccinated for chicken pox, rubella, and hepatitis B at least three months before trying to conceive.
First Trimester
•Limit stress. Severe stress during this time could heighten the chance that a baby will later become schizophrenic. You can't prevent most traumatic events, but don't work in a hostile environment if you don't have to.
•Avoid smog. Air pollutants like carbon monoxide and ozone have been linked to heart defects when the exposure coincided with the second month of pregnancy, when the heart is forming.
•Make a date with folate. Folic acid deficiency in the first 28 days of pregnancy leads to brain and spinal cord defects, so stock up on lentils, asparagus, and fortified cereal.
Second Trimester
•Be an iron woman. By the 20th week of pregnancy, your stored iron supply may be depleted, meaning you could get anemic. For the sake of your own energy and for your growing fetus, take a supplement and eat spinach.
•Stay off caffeine. You're not off the hook, Starbucks addicts: A large British study concluded that caffeine consumption during pregnancy was associated with smaller babies. The association continued all the way through pregnancy.
Third Trimester
•Don't forget choline. Your brain cell volume decreases during the third trimester, and you may be feeling a little spacey. Found in egg yolks, soybeans, and beef, choline can help boost your memory and aid in your baby's ongoing brain development.
•Meditate, do prenatal yoga, and breathe deeply to promote relaxation and increase the amount of oxygen that reaches the fetus. Your life is about to change drastically; don't stress out about having everything perfectly put together but do make sure you have social support lined up.
Source: http://www.psychologytoday.com/articles/200904/fateful-first-actA Fateful First Act
The action-packed days a baby spends in utero influence her emotional and physical makeup for years to come.
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