Transcript Slide 1

Chapter 15
Nutrition Prior to Pregnancy
 Nutrition can affect fertility
 Preparation before pregnancy
 Achieve and maintain healthy body weight
 Choose an adequate and balanced diet
 Take a multivitamin for the folate (one of the DGA’s)
 Be physically active
 Receive regular medical care
 Manage chronic conditions
 Avoid harmful influences (drugs, tobacco, excess alcohol)
Growth and Development
During Pregnancy
 Placental development
 Develops in uterus in the early days post-conception

Amniotic sac and umbilical cord
 Expelled during childbirth
 Interweaving of fetal and maternal blood vessels
delivering O2 and nutrients and carrying out waste
 Metabolically active organ:
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Yes, it’s an organ
Requires energy and nutrients
Produces hormones that maintain pregnancy and prep for
lactation
The Placenta and
Associated Structures
The arrows indicate the direction of blood flow.
Umbilical cord
Uterine wall
Placenta
Amniotic
sac
In the placenta, maternal
blood vessels lie side by
side with fetal blood vessels
that reach the fetus through
the umbilical cord.
Pool of mother's
Fetal artery
Fetal vein
blood
Fingerlike projections
(called placental villi)
contain fetal blood
vessels and extend
into the pool of
mother’s blood. No
actual mingling of
fetal and maternal
blood occurs, but
substances pass
back and forth.
Umbilical cord
Thus, oxygen and
nutrients from the
mother’s blood enter
fetal vessels, and
waste products are
removed.
Umbilical vein
Umbilical
arteries
Mother’s veins carry
fetal wastes away.
Fetal portion Maternal portion
of placenta
of placenta
Mother’s arteries
bring fresh blood
with oxygen and
nutrients to the fetus.
Growth and Development
During Pregnancy
 Fetal growth and development
 Fertilization of an ovum by a sperm
 Zygote during 1st week
 Rapid division to become blastocyst
 Implantation in uterine wall
 Embryo- 2-8 weeks
 1-1/4 inch at 8 weeks: has CNS, CVS, GI tract, fingers,
toes
 Fetus- 8-40 weeks
 Full-term at 38-42 weeks, avg. 6.5-8 lbs
Stages of Embryonic
and Fetal Development
1) A newly fertilized
ovum is about the size
of a period at the end of
this sentence. This
zygote at less than one
week after fertilization is
not much bigger and
is ready for implantation.
2) After implantation, the
placenta develops and
begins to provide
nourishment to the
developing embryo. An
embryo 5 weeks after
fertilization is about 1 / 2
inch long.
3) A fetus after 11 weeks of
development is just over
an inch long. Notice the
umbilical cord and blood
vessels connecting the
fetus with the placenta.
4) A newborn infant after
nine months of
development measures
close to 20 inches in
length. From 8 weeks to
term, this infant grew 20
times longer and 50 times
heavier.
Growth and Development
During Pregnancy
 Critical periods
 Times of intense development, rapid cell division
 Critical periods occur early in pregnancy

Certain cellular activities can occur only during these times
 Adverse influences on organ and tissue development

Each organ has its own critical period
An adverse influence felt
late temporarily impairs
development, but a full
recovery is possible.
Normal
development
An adverse
influence felt early
permanently impairs
development, and a
full recovery never
occurs.
Critical
period
Time
Critical Periods of Development
Growth and Development
During Pregnancy
 Neural tube defects – >300,000 births/yr worldwide
 1) Anacephaly

Brain either missing or fails to develop
 2) Spina bifida
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Incomplete closure of spinal cord & its bony encasement
Varying degrees of paralysis → death
Clubfoot, dislocated hip, curved spine, retardation, motor /sensory loss
• - Research on root causes: gene-gene, gene-nutrient, gene-
environment
 - Risk factors- family hx, maternal DM or obesity, anti-seizure meds,
mutation in folate-related enzymes
 - Folate supplementation 400 µg/d one month prior to conception and
through 1st trimester
 - Public health recommendation to “all women of childbearing age”
At 4 weeks, the neural tube has yet to
close (notice the gap at the top).
At 6 weeks, the neural tube (outlined by
the delicate red vertebral arteries) has
successfully closed.
Spina Bifida
Spina Bifida
Normal Spine
Meninges
Vertebra
Spinal cord
Spinal fluid
Spina Bifida
Spine
Spine
Growth and Development
During Pregnancy
 Chronic diseases cont’d
 Adverse influences at critical times during fetal development
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Malnutrition – folate deficiency
Type 2 diabetes
Maternal inadequate nutrition affects cardiovascular growth during
placental & gestational development → infant hypertension, lipid
metabolism, immune system → adult health
 Fetal programming
 Mother’s nutrition during pregnancy may change gene
expression in fetus, influence disease susceptibility later in life
Maternal Weight
 Birthweight is most reliable indicator of infant’s health
 Weight prior to conception
 Influences fetal growth
 Underweight

Higher rates of preterm births and infant deaths
 Overweight & obesity
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Higher risk of their own medical complicationshypertension, gestational DM, postpartum infections,
Risks for infant- NTD from maternal poor glycemic control,
heart defects and other abnormalities, infant wt >9 lbs from
diabetic mother- caesarean section
Maternal Weight
 Weight gain during pregnancy- only 1/3 gain the right
amount; most gain more
 Fetal growth and maternal health
 Correlates closely with infant birthweight

Predictor of health and development
 Recommended weight gains- see the chart

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Number of fetuses
Beginning weight
Recommended Weight Gains
Maternal Weight
 Weight gain patterns
 3.5 pounds in first trimester
 1 pound per week thereafter
 Large weight gain over short time

Preeclampsia
 Components of weight gain
 Placenta, uterus, blood, breasts, fluid volume, baby

Maternal fat stores
Weight
gain (lb)
1st trimester
2nd trimester
3rd trimester
Increase in
breast size
2
Increase
mother's
fluid volume
4
Placenta
1 1/2
Increase in
blood supply
to the placenta
4
Amniotic fluid
2
Infant at birth
7 1/2
Increase in size
of uterus and
supporting
muscles
Mother's
necessary
fat stores
2
7
30
Stepped Art
Maternal Weight
 Weight loss after pregnancy
 Return to prepregnancy weight

Ideal but not typical
 Retain a couple of pounds fat with each pregnancy


Seven or more pounds, BMI increased 1 unit risks diabetes and
hypertension
Chronic diseases later in life for mother and infant
 Losing the pregnancy weight indicates better success at
maintaining middle age weight
Exercise During Pregnancy
 Can continue “moderate intensity” exercise throughout
pregnancy 30 min/session
 Do regularly and adjust duration and intensity as needed
 “Low-impact” activities like swimming, walking
 Benefits
 Less diabetes, easier labor
 Protect fetal development with Exercise “Don’ts”
 Stay out of saunas, hot humid weather.
 Keep hydrated
Don’t push yourself.
 No contact sports
No exercise on your back
 Stop if painful
No bouncy jerky exercise
DO
DON’T
Do begin to
exercise gradually.
Don’t exercise
vigorously after long
periods of inactivity.
Do exercise regularly
(most, if not all, days
of the week).
Don’t exercise in
hot, humid weather.
Do warm up with 5 to 10
minutes of light activity.
Don’t exercise when
sick with fever.
Do 30 minutes or more
of moderate physical
activity; 20 to 60 minutes
of more intense activity
on 3 to 5 days a week will
provide greater benefits.
Don’t exercise while
lying on your back
after the first trimester
of pregnancy or stand
motionless for
prolonged periods.
Pregnant women can enjoy
the benefits of exercise.
Do cool down with 5 to 10
minutes of slow activity
and gentle stretching.
Don’t exercise if you
experience any pain,
discomfort, or fatigue.
Do drink water
before, after, and
during exercise.
Don’t participate in
activities that may
harm the abdomen or
involve jerky, bouncy
movements.
Do eat enough to
support the needs
of pregnancy plus
exercise.
Do rest adequately.
Safe exercise during pregnancy
Energy & Nutrient Needs
During Pregnancy
 Nutrient needs tend to be higher than any other time
in life.
 To meet needs
 Make nutrient-dense selections
 Body maximizes absorption, minimizes losses
 Fe, folate, Ca especially important
Energy & Nutrient Needs
During Pregnancy
 Energy
 Increase in basal metabolic rate
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1st trimester- usual kcal, focus on getting ALL micronutrients
2nd trimester add 340 kcal/d
3rd trimester add 450 kcal/d
 Food energy
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Need 15 to 20% more energy than before pregnancy
Nutrient-dense foods
Energy & Nutrient Needs
During Pregnancy
 Carbohydrate
 Ample carbohydrate is necessary
 Protein
 RDA – additional 25 grams per day
 Essential fatty acids
 Omega-3 and omega-6 fatty acids needed for developing
brain material (make a smart baby now)
Energy & Nutrient Needs
During Pregnancy
 Fetal blood production and cell growth (DNA)
and maternal red blood cell mass
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Folate 600 μg/d
Vitamin B12 2.6 μg/d
Iron 27 mg/d
Zinc 12 mg/d
 Benefits of prenatal supplements: Drugstore prenatal OK
 Intentionally eat well. The pill can only do so much.
Energy & Nutrient Needs
During Pregnancy
 Nutrients for bone development
 Protect your own bones from “borrowing”
 Vitamin D

Deficiency interferes with calcium metabolism
 Calcium
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Absorption and retention increase
Intake usually falls below recommendations
 Other nutrients

Optimal interval between pregnancies
Vegetarian Diets During
Pregnancy & Lactation
 Can support healthy pregnancy and lactation
 Must be planned and disciplined
 Should include dairy and eggs
 Variety of whole foods
 Additional supplementation- B12, Fe, Ca, D
 Focus on COMPLETE proteins (complementary)
 Vegan diets – NO!!
NO!!
NO!!
NO!!!
 Risks- too many to list, long-term and irreversible
effects a real potential
Common Nutrition-Related
Concerns of Pregnancy
 Nausea
 “Morning sickness” to can’t keep anything down
 Try a 50 mg B6 pill from weeks 6-14
 http://www.morningsicknesshelp.com/morningsickness-cure.html
 Constipation and hemorrhoids
 Heartburn
 Food cravings and aversions
 Hormone-induced changes
 Nonfood cravings- pica
High-Risk Pregnancies
 Infant’s birthweight
 Low birthweight (LBW)
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5 ½ pounds or less
Risk of complications
Relationship with socioeconomic status
 Gestational age
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Preterm
Small-for-gestational age
High-Risk Pregnancies
 Malnutrition and pregnancy
 Fertility
 Early, unplanned pregnancy
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Poor placental development can affect fetus’s future children
 Fetal development
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Consequences
 Retardation, birth defects, miscarriages, stillbirths, infant
mortality 0-4 yrs.
High-Risk Pregnancies
 Food Assistance Programs
 WIC
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Nutrition education and nutritious foods
Vulnerable populations who qualify for help
Cost-benefit
Remedial and preventive services
High-Risk Pregnancies
 Maternal age
 Ideal childbearing age 20-25, up to 35 yrs OK
 Adolescents
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Risk of pregnancy complications
Higher rates of stillbirths, preterm births, and LBW infants
Weight gain recommendations
Imperative need to seek prenatal care
High-Risk Pregnancies
 Maternal age
 Women older than 35 yrs
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Complications often reflect chronic conditions
Cesarean section rates increase
Maternal death rates are higher
Risks for fetus
Down’s syndrome 1/100 for 40 yr old vs. 1/10,000 for 20 yr old
High-Risk Behaviors
 Alcohol consumption
 Irreversible mental and physical retardation

Fetal alcohol syndrome (FAS)
 Medicinal drugs
 No medication use without consulting physician
 Herbal supplements
 Seek physician advice
High-Risk Behaviors
 Illicit drugs
 Many drugs easily cross the placenta

Impair fetal growth and development
 Other risks to fetus, infant, and child
 Smoking and chewing tobacco
 Harmful effects magnified during pregnancy
 Risks for mother and infant

SIDS
High-Risk Behaviors
 Exposure to environmental contaminants
 Lead
 Mercury
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Foods to avoid-shark, swordfish, king mackerel, tilefish
Supplements
 Foodborne illness
 No raw milk or dairy, undercooked eggs, meat or
chicken, no sprouts
 Increased risk of listeriosis
 Risks associated with illness- meningitis, pneumonia,
miscarriage
High-Risk Behaviors
 Vitamin-mineral megadoses
 Excessive vitamin A (B6 for morning sickness OK)

Fetal malformations
 Caffeine
 Miscarriage and fetal death
 Fetal growth
 Weight-loss dieting
 Sugar-substitutes
Short List
 Good nutrition and health prior to pregnancy
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And prenatal care during pregnancy
Gain a healthy amount of weight
Eat a balanced diet, no risky foods
Regular low-impact exercise
Take prenatal vitamin and mineral supplement
No smoking, drinking, drugs, herbs
Lactation: A Physiological Process
 Hormones promote growth and branching of duct
system & milk-producing cells
 Prolactin

Milk production
 Oxytocin

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Cause mammary glands to eject milk into ducts
Let-down reflex
Breastfeeding: A Learned Behavior
 Lactation is an automatic, physiological process
 Breastfeeding is a learned behavior
 Some decide not to breastfeed
 La Leche League International- THE experts
 Breastfeeding report (p. 28)
 Factors influencing breastfeeding and its success
 Father
 Adequate nutrition and rest
Maternal Energy & Nutrient Needs
During Lactation
 Energy intake (~1800 kcal/d total) and exercise
 Almost 500 extra kcal per day needed to produce
25 oz milk
 Mother can eat 330 kcal extra and let body fat provide
the rest. DGA: Moderate weight loss is OK
 Exercise is compatible with breastfeeding
 Energy nutrients
 Recommendations increase for carbohydrates and fibers
 Water
 Prevent dehydration
Maternal Energy & Nutrient Needs
During Lactation
 Vitamins and minerals
 Inadequacies reduce the quantity, not quality of breast
milk

Quality maintained at expense of maternal stores, though this
varies by nutrient
 Prolonged inadequate intakes

Impacts several nutrients- calcium, B6, B12, A, D
 Supplements
 Iron to replete anemia in pregancy
 Finish up the bottle of prenatal MVI
Maternal Energy & Nutrient Needs
During Lactation
 Food assistance programs
 Free formula
 Participants are less likely to breastfeed
 WIC incentives to encourage breastfeeding

higher priority, longer certification, more foods & quantity,
free breast pump
 Particular foods
 Strong flavors getting into the milk
 Infant w/family history of allergies needs to breastfeed
Maternal Health
 HIV infection and AIDS
 HIV virus transmissable through breastmilk
 Developing countries: Formula made with contaminated
water causes 1.5 million infant deaths/yr

Medications
 Diabetes – type I
 Postpartum amenorrhea
 Does not protect from pregnancy
 Breast health
 Protective for breast cancer
Practices Incompatible
With Lactation
 Alcohol
 Easily enters breast milk
 Infants eat less when mother consumes alcohol
 Medical drugs
 Physician consultation
 Illicit drugs
 Risks
Practices Incompatible
With Lactation
 Smoking
 Reduces milk volume
 Sleep less
 Passive smoking and SIDS
 Environmental contaminants
 DDT, PCBs, and dioxin
 Caffeine
 Iron bioavailability