MATERNAL and INFANT NUTRITION

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MATERNAL and INFANT
NUTRITION
Stages of Fetal Development
• A newly fertilized ovum (zygote)
begins as a single cell, and divides to
become many cells during the days
after fertilization
• Within 2 weeks, the zygote embeds
itself into the uterine wall
(implantation)
Stages of Fetal Development
•
•
•
After implantation, the placenta develops and
begins to provide nourishment to the developing
embryo
The placenta develops inside the uterus, and it
provides nutrients and oxygen, as well as a way for
the developing embryo to return carbon dioxide
and other wastes to be excreted
An embryo at 5 weeks after fertilization is ~ ½ an
inch long
Stages of Fetal Development
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•
•
At 8 weeks, the 1¼ inch long embryo has a
complete nervous system, a beating heart, a
digestive system, well-defined fingers, and
toes, and the beginnings of facial features
The fetus continues to grow during the next
7 months
Fetal growth is phenomenal – weight
increase from less than an ounce to ~ 7.5
pounds
Critical Periods
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•
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Times of intense development and rapid cell
division are called critical periods (cellular
activities can only occur at these times)
Each tissue and organ is most vulnerable to
adverse influences during its own critical period
Adverse influences include nutrient deficiencies or
toxins
An adverse influence felt early = irreversibly
impairs development
An adverse influence felt late = may only
temporarily impair development
Critical Periods
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Critical period for neural tube development
is 17 to 30 days gestation – folate
supplementation reduces the risk for neural
tube defects
The brain and spinal cord develop from the
neural tube, and defects in its orderly
formation during the early weeks of
pregnancy may result in various central
nervous system disorders (spina bifida)
Critical Periods
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•
Maternal anemia during the critical period
of placental growth alters the pattern of
blood vessel growth, which may affect the
cardiovascular health of the infant
Malnutrition during the critical period of
pancreatic cell growth may contribute to the
development of diabetes in adulthood
MATERNAL WEIGHT
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•
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A woman’s weight prior to conception
influences fetal growth
Underweight: higher risk of a LBW infant,
higher risk of a preterm infant
Overweight: higher risk of medical
complications such as hypertension, gestational
diabetes, and postpartum infections. Also since
the baby may be larger then normal - may lead
to difficult labor, delivery, and birth trauma
However, weight loss during pregnancy is
NEVER advisable
Weight Gain During Pregnancy
•
•
All pregnant women must gain weight –
fetal growth depends on it
Maternal weight gain during pregnancy
correlates closely with infant birthweight,
which is a strong predictor of the health of
the infant
Weight Gain During Pregnancy
Prepregnancy Weight Recommended
Status
Weight Gain
Underweight (BMI<19.8)
28 to 40 pounds
Normal Weight (BMI 19.0-26)
25 to 35 pounds
Overweight (BMI 26-29)
15 to 25 pounds
Obese (BMI >29)
15 pounds minimum
Weight Gain Patterns
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•
•
Normal weight women should gain ~3
lbs. in the first trimester, and just under
1 lb/week thereafter
Underweight women: 1st trimester = 5
lbs., 1 lb/week thereafter
Overweight women: 1st trimester = 2
lbs., 2/3 lb/week thereafter
Components of Weight Gain
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•
Most of the weight gain supports the growth
and development of the placenta, uterus,
blood, and breasts, as well as an optimally
healthy infant
A small amount goes into maternal fat
stores, and that fat has a special purpose: to
provide energy for labor and lactation
Weight Loss After Pregnancy
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•
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The pregnant women loses some weight at
delivery
In the following weeks, she loses more as her
blood volume returns to normal and she sheds
accumulated fluids
The typical women does not return to
prepregnancy weight, most tend to retain a
couple of pounds with each pregnancy
In general, the more weight a women gains
beyond the needs of pregnancy, the more she
will retain
Nutrition During Pregnancy
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•
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From conception to birth, all parts of the
infant – bones, muscles, organs, skin, and
other tissues – are made from the nutrients
in the food that mother eats
ENERGY: extra 340 calories in the 2nd and
extra 450 calories in the 3rd trimester
PROTEIN: 25 grams per day higher than
the RDA (most are already getting that)
Nutrition During Pregnancy
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•
ESSENTIAL FATTY ACIDS: the
brain is largely made up of lipid
material, and it depends highly on the
omega 3 and omega 6 fatty acids for its
growth, function, and structure
Pregnant women are advised to include
seafood, leafy greens, nuts, and seeds
in their diet
Mercury in Fish
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•
•
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FDA has issued an advisory to all pregnant
women, women who may become pregnant,
lactating mothers, and young children – avoid
eating large amounts of mackerel, swordfish,
shark, tuna, and tilefish
Pregnant and lactating women – one can of tuna
per week
Young children – less than a can per month
http://www.doh.wa.gov/fish/FishAdvWomen.htm
Nutrition During Pregnancy
Nutrients for:
• Blood production and cell growth – folate,
B12, iron, and zinc
• Bone development – vitamin D, calcium,
phosphorus, magnesium, and fluoride
Supplementation
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•
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Women who make wise food choices during
pregnancy can meet most of their nutrient needs,
however, iron and folate are two nutrients that
may need to be supplemented
Women of childbearing age who are capable of
becoming pregnant are advised to consume 400
micrograms of folate per day (supplements are
convenient, better absorbed)
Iron supplements are recommended during the 2nd
and 3rd trimesters of pregnancy (30 mg per day)
Nutrition-Related Concerns
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•
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Nausea – hormonal changes appear to be
responsible for a woman’s sensitivities to
the appearance, smell, or taste of foods
Suggestions:
On waking, arise slowly
Eat small, frequent meals
Avoid foods with offensive odors
When nauseated do not drink citrus juice,
milk, coffee, or tea
Nutrition-Related Concerns
•
•
•
•
•
Constipation – as the hormones of
pregnancy alter muscle tone and the
growing fetus crowds the intestinal
organs
Suggestions:
Eat foods high in fiber
Exercise regularly
Drink plenty of fluids
Nutrition-Related Concerns
•
•
•
•
•
•
•
•
Heartburn – the hormones relax the digestive
muscles, and the growing fetus puts increased
pressure on the mother’s stomach
Suggestions:
Relax and eat slowly
Chew food thoroughly
Eat small, frequent meals
Avoid spicy or greasy foods
Sit up while eating, elevate head when
sleeping
Wait an hour after eating before lying down
Gestational Diabetes
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A condition of abnormal glucose tolerance,
usually during the second half of pregnancy,
which resolves after birth
Consequences of GD – complications during
delivery, high infant birthweight, and birth
defects (heart damage, limb deformities, and
neural tube defects)
Risk Factors: age, obesity, family history,
history of abnormal glucose tolerance,
ethnicity associated with a high incidence of
diabetes
Practices Incompatible with
Pregnancy
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Alcohol – limits oxygen delivery, slows cell
division
Medicinal and illicit drugs
Tobacco – linked to premature labor, breathing
problems, and fatal illness among infants
Environmental contaminants
Vitamin-Mineral megadoses
Caffeine
Weight-loss dieting
Low Birthweight
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Low birthweight (less than 5.5 lbs. or 2500
grams) is the factor most associated with infant
mortality.
Babies who are low birthweight are 40 times
more likely to die in their first year than healthy
babies.
Those who survive are more vulnerable to serious
health and developmental problems, such as
blindness, deafness, mental retardation and
learning disabilities.
Causes of Low Birthweight Infants
Poor nutrition
 Genetics
 Disease conditions
 Smoking
 Drug use (including alcohol)

LACTATION
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Lactation is an automatic process that
virtually all mothers are capable of
doing
Breastfeeding is a learned behavior
The United States Lags in Breastfeeding
The United States has one of the lowest rates of
breastfeeding in the industrialized world, and one
of the highest rates of infant mortality
Data from 1998 indicate that only 64 percent of U.S.
mothers initiate breastfeeding, and only 29 percent
report feeding any human milk to their infants at
six months.
Those numbers stand in marked contrast to Sweden,
for example, where the breastfeeding initiation
rate exceeds 98 percent and the rate at six months
is 80 percent.

What are the barriers to breastfeeding in the
US?
BENEFITS of
BREASTFEEDING
For Infants:
• Provides the perfect balance of nutrients
with high bioavailability
• Provides hormones that promote
physiological development
• Improves cognitive development
• Protects against a variety of infections
• May protect against some chronic diseases
(IDDM, hypertension)
• Protects against food allergies
BENEFITS of
BREASTFEEDING
For Mothers
• Contracts the uterus
• Delays the return of regular ovulation
• Conserves iron stores (by prolonging amenorrhea)
• May protect against breast cancer
• May help the mother to lose weight gained during
pregnancy (~650 cal/day)
• It’s cheap! (A nursing mother produces over 35
gallons of milk during the first six months, saving
~$450 in formula costs)
Composition of Breast Milk
Composition of Breast Milk
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Lipids: triglycerides are the major energy
source, also rich in cholesterol, EFAs(EPA,
and DHA)
Carbohydrates: lactose is the major CHO
Proteins: Whey proteins predominate, all
essential amino acids, lactoferrin (protects
infants from infection), other
immunoglobulins (antibodies)
Composition of Breast Milk
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Vitamins and Minerals: a perfect balance of
all essential vitamins and minerals
Other: digestive enzymes, anti-infective
factors, hormones, and growth factors
Nutrient Needs During Lactation
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Energy RDA during lactation – extra 500 kcal/day
(1800 kcal/day minimum)
Protein RDA during lactation – same as during
pregnancy
Vitamins and Minerals – milk quality is maintained
at the expense of the maternal stores
Nutrients in breast milk most likely to decline in
response to inadequate stores are – B6, B12,
Vitamin A and D
In general, nutritional inadequacies reduce the
quantity, not the quality of breast milk
High Protein Diets
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•
There are some concerns that it is not safe
for a breastfeeding mother to be in ketosis
The Atkins Center website’s recommends
that pregnant and breastfeeding women
adjust their carbohydrate intake to
maintenance level (enough carbohydrate to
decrease ketone production)
Nutrition During Infancy
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•
Solid foods are introduced based on an
infant’s physiological needs, such as
depletion of iron stores, and on physical
development, such as the ability to sit up
Current recommendation: 4 to 6 months
Foods To Omit
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Concentrated sweets
Canned vegetables
Honey and corn syrup
Popcorn, whole grapes, whole beans, hot
dog slices, hard candies, and nuts
Cow’s milk (before 12 months)
Food Allergies
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•
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Experts recommend introducing single-ingredient
foods, one at a time, in small portions, and waiting
4 to 5 days to introduce the next food (rice cereal barley - oats - wheat)
A true food allergy occurs when protein fractions
of a food are absorbed into the blood and elicit an
immunological response (antibodies, histamines,
or other defensive agents)
Food intolerances involve symptoms, but no
antibodies
Iron Deficiency
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Iron deficiency has a well-known and wide
spread effect on children’s behavior
Symptoms include decreased energy,
learning ability, attention span, and
depressed mood
The long-term damaging effects of iron
deficiency make its prevention a high
priority
Nutrition During Infancy
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•
•
The two dietary practices that have the most
effect on an infant’s nutrition status are the
milk the infant receives and the age at
which solid foods are introduced
Breast feeding is recommended for at least
6 months, but even 2 to 3 months can give
the infant immunological protection
Breast milk is the prefect infant food, but
iron, Vitamin D, fluoride, and Vitamin K
may need to be supplemented
Lead Toxicity
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•
Children who are malnourished are
vulnerable to lead poisoning (they absorb
more lead if their stomachs are empty, and
if they have iron deficiencies)
Lead toxicity is most prevalent in children
under 6, and 10-15% of all preschoolers
may have blood lead concentrations high
enough to cause mental, behavioral, and
other health problems
Lead Toxicity
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•
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Lead is present in old homes (plumbing),
old paint, and in some soil
Children can ingest lead by drinking
contaminated water, eating paint chips,
playing in and around lead contaminated
house dust or soil
Lead is not easily excreted and accumulates
in the bones, brain, teeth, and kidneys
Deficits in intellectual development are only
partially reversed when lead levels decline
Prevalence of Eating Disorders
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More than 5 million Americans suffer from eating
disorders
90% of cases of anorexia and bulimia occur in
females
15% of young women have substantially
disordered eating attitudes or behaviors
8% of overweight women and 30% of those
seeking treatment from weight loss programs meet
criteria for binge eating disorder; 25% of binge
eaters may be male
What Causes Eating Disorders?
Nutrition-Related Concerns
•
•
•
•
•
•
Nausea – hormonal changes appear to be
responsible for a woman’s sensitivities to
the appearance, smell, or taste of foods
Suggestions:
On waking, arise slowly
Eat small, frequent meals
Avoid foods with offensive odors
When nauseated do not drink citrus juice,
milk, coffee, or tea
Nutrition-Related Concerns
•
•
•
•
•
•
Nausea – hormonal changes appear to be
responsible for a woman’s sensitivities to
the appearance, smell, or taste of foods
Suggestions:
On waking, arise slowly
Eat small, frequent meals
Avoid foods with offensive odors
When nauseated do not drink citrus juice,
milk, coffee, or tea
Nutrition-Related Concerns
•
•
•
•
•
Constipation – as the hormones of
pregnancy alter muscle tone and the
growing fetus crowds the intestinal
organs
Suggestions:
Eat foods high in fiber
Exercise regularly
Drink plenty of fluids
Nutrition-Related Concerns
•
•
•
•
•
•
•
•
Heartburn – the hormones relax the digestive
muscles, and the growing fetus puts increased
pressure on the mother’s stomach
Suggestions:
Relax and eat slowly
Chew food thoroughly
Eat small, frequent meals
Avoid spicy or greasy foods
Sit up while eating, elevate head when
sleeping
Wait an hour after eating before lying down
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