life cycle nutrition: pregnancy and lactation

Life Cycle Nutrition: Life Cycle Nutrition: Pregnancy and LactationPregnancy and Lactation

Chapter 15

Nutrition Prior to Nutrition Prior to PregnancyPregnancy

• 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 Growth and Development During PregnancyDuring 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 Growth and Development During PregnancyDuring 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 Growth and Development During PregnancyDuring 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 Growth and Development During PregnancyDuring 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 Growth and Development During PregnancyDuring 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 WeightMaternal 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 WeightMaternal 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 Recommended Weight GainsGains

Maternal WeightMaternal 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 WeightMaternal 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 PregnancyExercise 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 Energy & Nutrient Needs During PregnancyDuring 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 Energy & Nutrient Needs During PregnancyDuring 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 Energy & Nutrient Needs During PregnancyDuring 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 Energy & Nutrient Needs During PregnancyDuring Pregnancy

• Blood production and cell growth– Fetal growth and development– Maternal red blood cell mass– Needs for synthesis of DNA and new cells

• Folate• Vitamin B12

• Iron• Zinc

Energy & Nutrient Needs Energy & Nutrient Needs During PregnancyDuring 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 Energy & Nutrient Needs During PregnancyDuring Pregnancy

• Prenatal supplements– Calcium– Folate– Iron

• Benefits of use

Vegetarian Diets During Vegetarian Diets During Pregnancy & LactationPregnancy & Lactation

• Can support healthy pregnancy and lactation– Well planned– Food sources

• Vegan diets – Additional supplementation

Common Nutrition-Related Common Nutrition-Related Concerns of PregnancyConcerns of Pregnancy

Nausea “Morning sickness” Hormonal changes

Constipation and hemorrhoids Heartburn Food cravings and aversions

Hormone-induced changes Nonfood cravings

High-Risk PregnanciesHigh-Risk Pregnancies Infant’s birthweight

Low birthweight (LBW) 5 ½ pounds or less Risk of complications Relationship with socioeconomic status

Gestational age

High-Risk PregnanciesHigh-Risk Pregnancies• Malnutrition and pregnancy

– Fertility• Viable sperm• Sexual interest• Amenorrhea

– Early pregnancy• Placenta development

– Fetal development• Consequences

High-Risk PregnanciesHigh-Risk Pregnancies• Food Assistance Programs

– WIC• Nutrition education and nutritious foods• Vulnerable populations who qualify for help• Cost-benefit• Remedial and preventive services

High-Risk PregnanciesHigh-Risk Pregnancies• Maternal health

– Preexisting diabetes• Risks associated with unmanaged diabetes

– Gestational diabetes• Common consequences• Dietary recommendations

High-Risk PregnanciesHigh-Risk Pregnancies• Maternal health

– Chronic hypertension• Risks

– Gestational hypertension– Preeclampsia

• Cause is unclear• Risks for mother• Risks for fetus

– Eclampsia

High-Risk PregnanciesHigh-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 PregnanciesHigh-Risk Pregnancies• Maternal age

– Older women• Complications often reflect chronic conditions• Cesarean section rates increase • Maternal death rates are higher• Risks for fetus

High-Risk PregnanciesHigh-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 PregnanciesHigh-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 PregnanciesHigh-Risk Pregnancies• Environmental contaminants

– Lead– Mercury

• Foods to avoid• Supplements

• Foodborne illness– Increased risk of listeriosis– Risks associated with illness

High-Risk PregnanciesHigh-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 Lactation: A Physiological ProcessProcess

• 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 Breastfeeding: A Learned BehaviorBehavior

• 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 Maternal Energy & Nutrient Needs During LactationNeeds 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 Maternal Energy & Nutrient Needs During LactationNeeds 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 Maternal Energy & Nutrient Needs During LactationNeeds During Lactation

• Food assistance programs– Participants are less likely to breastfeed – WIC incentives to encourage breastfeeding

• Particular foods– Flavors– Allergies

Maternal HealthMaternal 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 Practices Incompatible With LactationLactation

• Alcohol– Easily enters breast milk– Infants eat less when mother consumes alcohol

• Medical drugs– Physician consultation

• Illicit drugs– Risks

Practices Incompatible With Practices Incompatible With LactationLactation

• Smoking– Reduces milk volume– Sleep less– Passive smoking and SIDS

• Environmental contaminants– DDT, PCBs, and dioxin

• Caffeine– Iron bioavailability