Life Cycle Nutrition: Pregnancy and Lactation
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Transcript Life Cycle Nutrition: Pregnancy and Lactation
Life Cycle Nutrition:
Pregnancy and Lactation
Chapter 15
Nutrition Prior to Pregnancy
• Nutrition may affect fertility
• Preparation before pregnancy
– Achieve and maintain healthy body weight
– Choose an adequate and balanced diet
– Be physically active
– Receive regular medical care
– Manage chronic conditions
– Avoid harmful influences
Growth and Development During
Pregnancy
• Placental development
– Develops in uterus
• Amniotic sac and umbilical cord
– Expelled during childbirth
– Interweaving of fetal and maternal blood vessels
– Metabolically active organ
• Requires energy and nutrients
• Produces hormones
Growth and Development During
Pregnancy
• Fetal growth and development
– Fertilization of an ovum by a sperm
– Zygote
• Rapidly divides to become blastocyst
• Implantation
– Embryo
• Eight weeks
– Fetus
• Full-term
Growth and Development During
Pregnancy
• Critical periods
– Times of intense development
• Cellular activities can occur only during these times
– Adverse influences on organ and tissue
development
Growth and Development During
Pregnancy
• Neural tube defects
– Anacephaly
• Brain either missing or fails to develop
– Spina bifida
• Incomplete closure of spinal cord & its bony
encasement
– Folate supplementation
Growth and Development During
Pregnancy
Chronic diseases
Adverse influences at critical times during
fetal development
Malnutrition – type 2 diabetes
Inadequate growth during placental & gestational
development – hypertension
Fetal programming
Mother’s nutrition may change gene
expression in fetus
Maternal Weight
Birthweight is most reliable indicator of
infant’s health
Weight prior to conception
Influences fetal growth
Underweight
Rates of preterm births and infant deaths
Overweight & obesity
Medical complications
Risks for infant
Maternal Weight
• Weight gain during pregnancy
– Fetal growth and maternal health
– Correlates closely with infant birthweight
• Predictor of health and development
– Recommended weight gains
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 Weight
• Weight loss after pregnancy
– Return to prepregnancy weight
• Not typical
– Retain a couple of pounds with each pregnancy
– Seven or more pounds; BMI increase 1 unit
Exercise During Pregnancy
Can continue exercise throughout
pregnancy
Adjust duration and intensity
Benefits
“Low-impact” activities
Fetal development
Excessively high internal body temperature
Dehydration
Energy & Nutrient Needs During
Pregnancy
• Needs tend to be higher than any other time
in life
• To meet needs
– Make careful selections
– Body maximizes absorption
– Body minimizes losses
Energy & Nutrient Needs During
Pregnancy
• Energy
– Increase in basal metabolic rate
• Second and third trimester
– Food energy
• 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
Supplements are discouraged
Essential fatty acids
Omega-3 and omega-6 fatty acids for brain
material
Energy & Nutrient Needs During
Pregnancy
• Blood production and cell growth
– Fetal growth and development
– Maternal red blood cell mass
– Needs for synthesis of DNA and new cells
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Folate
Vitamin B12
Iron
Zinc
Energy & Nutrient Needs During
Pregnancy
• Nutrients for bone development
– Vitamin D
• Deficiency interferes with calcium metabolism
– Calcium
• Absorption and retention increase
• Intake usually falls below recommendations
– Other nutrients
• Optimal interval between pregnancies
Energy & Nutrient Needs During
Pregnancy
• Prenatal supplements
– Calcium
– Folate
– Iron
• Benefits of use
Vegetarian Diets During Pregnancy
& Lactation
• Can support healthy pregnancy and lactation
– Well planned
– Food sources
• Vegan diets
– Additional supplementation
Common Nutrition-Related
Concerns of Pregnancy
Nausea
“Morning sickness”
Hormonal changes
Constipation and hemorrhoids
Heartburn
Food cravings and aversions
Hormone-induced changes
Nonfood cravings
High-Risk Pregnancies
Infant’s birthweight
Low birthweight (LBW)
5 ½ pounds or less
Risk of complications
Relationship with socioeconomic status
Gestational age
High-Risk Pregnancies
• Malnutrition and pregnancy
– Fertility
• Viable sperm
• Sexual interest
• Amenorrhea
– Early pregnancy
• Placenta development
– Fetal development
• Consequences
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 health
– Preexisting diabetes
• Risks associated with unmanaged diabetes
– Gestational diabetes
• Common consequences
• Dietary recommendations
High-Risk Pregnancies
• Maternal health
– Chronic hypertension
• Risks
– Gestational hypertension
– Preeclampsia
• Cause is unclear
• Risks for mother
• Risks for fetus
– Eclampsia
High-Risk Pregnancies
• Maternal age
– Ideal childbearing age
– Adolescents
• Risk of pregnancy complications
• Higher rates of stillbirths, preterm births, and LBW
infants
• Weight gain recommendations
• Need to seek prenatal care
High-Risk Pregnancies
• Maternal age
– Older women
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Complications often reflect chronic conditions
Cesarean section rates increase
Maternal death rates are higher
Risks for fetus
High-Risk Pregnancies
• 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 Pregnancies
• 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 Pregnancies
• Environmental contaminants
– Lead
– Mercury
• Foods to avoid
• Supplements
• Foodborne illness
– Increased risk of listeriosis
– Risks associated with illness
High-Risk Pregnancies
• Vitamin-mineral megadoses
– Excessive vitamin A
• Fetal malformations
• Caffeine
– Miscarriage and fetal death
– Fetal growth
• Weight-loss dieting
• Sugar-substitutes
Lactation: A Physiological Process
• Hormones promote growth and branching of
duct system & milk-producing cells
– Prolactin
• Milk production
– Oxytocin
• Cause mammary glands to eject milk into ducts
Breastfeeding: A Learned Behavior
• Lactation is an automatic, physiological
process
• Breastfeeding is a learned behavior
– Some decide not to breastfeed
• Factors influencing breastfeeding and its
success
– Partner
– Adequate nutrition and rest
Maternal Energy & Nutrient Needs
During Lactation
• Energy intake and exercise
– Almost 500 extra kcalories per day
– 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
– Prolonged inadequate intakes
• Impacts several nutrients
• Supplements
– Iron
Maternal Energy & Nutrient Needs
During Lactation
• Food assistance programs
– Participants are less likely to breastfeed
– WIC incentives to encourage breastfeeding
• Particular foods
– Flavors
– Allergies
Maternal Health
HIV infection and AIDS
Transmission through breastmilk
Medications
Diabetes – type I
Postpartum amenorrhea
Does not protect from pregnancy
Breast health
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