Download Chapter 5 Nutrition during Pregnancy: Conditions and Interventions

Chapter 5
Nutrition During Pregnancy:
Conditions and Interventions
Nutrition Through the Life Cycle
Judith E. Brown
Introduction
• Health conditions impacting pregnancy &
interventions are covered to include:
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Hypertensive disorders of pregnancy
Preexisting & gestational diabetes
Obesity
Multifetal pregnancies
HIV/AIDS
Eating disorders
Fetal alcohol spectrum
Adolescent pregnancy
Hypertensive Disorders of
Pregnancy
• Hypertension (HTN) is defined as blood
pressure ≥140 mm Hg systolic or ≥90 mm
Hg diastolic blood pressure
– Affects 6 to 10% of pregnancies
– Contributes to stillbirths, fetal & newborn
deaths, & other adverse conditions
• “Pregnancy-induced hypertension” is being
replaced with “hypertensive disorders of
pregnancy”
Hypertensive Disorders of
Pregnancy
Hypertensive Disorders of
Pregnancy, Oxidative Stress, and
Nutrition
• HTN in pregnancy is related to:
– Inflammation
– Oxidative stress
– Damage to the endothelium (cells lining the
inside of blood vessels)
• Consequences of endothelial dysfunction:
– Impaired blood flow
– Increased tendency to clot
– Plaque formation
Ways to Reduce Oxidative Stress
• Regular intake colorful fruits and
vegetables, dried beans and whole-grain
products
• Adequate intake of vitamin D, & omega-3
fatty acids
• Ample physical activity
– Weight loss if overweight (not recommended
during pregnancy)
See Table 5.3.
Chronic Hypertension
• HTN present before pregnancy or diagnosed <20
weeks
• Estimated incidence is 1 to 5%
• More common in:
– African American, obese, >35 years of age, or
history of HTN with previous pregnancy
• Blood pressure ≥ 160/110 mm Hg associated with
increased risk of:
– Fetal death, preterm delivery, & fetal growth
retardation
Nutritional Interventions for
Women with Chronic
Hypertension in Pregnancy
– Intervention should aim to achieve adequate &
balanced diets for pregnancy
– Weight gain is same as for other pregnant
women
– If salt-sensitive, Na restriction required for
blood pressure control without too little that
could impair fetal growth
Gestational Hypertension
– Hypertension diagnosed for first time after 20
weeks of pregnancy
– No proteinuria
– Tend to be overweight or obese with excess
central body fat
Preeclampsia-Eclampsia
– A pregnancy-specific syndrome occurring >20
weeks gestation accompanied by proteinuria
• Proteinuria—urinary excretion of ≥0.3 gram protein
in 24-hour urine sample (or >30 mg/dL protein or
≥2 on dipstick reading)
• Eclampsia—occurrence of seizures not attributed to
other causes
Characteristics of PreeclampsiaEclampsia
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Oxidative stress, inflammation, & endothelial dysfunction
Blood vessel spasms & constriction
Increased blood pressure
Adverse maternal immune system responses to the
placenta
• Platelet aggregation & blood coagulation due to deficits in
prostacyclin relative to thromboxane
• Insulin resistance
• Elevated blood levels of triglycerides, free fatty acids and
cholesterol
Characteristics of PreeclampsiaEclampsia
• Signs and symptoms of preeclampsia range from
mild to severe
• Health consequences also range from mild to
severe
• Cause is unknown – appears to originate from:
– Abnormal implantation & vascularization of
placenta with poor blood flow.
Characteristics of PreeclampsiaEclampsia
Characteristics of PreeclampsiaEclampsia
Pregnancy After Bariatric
Surgery
• Bariatric surgery for weight loss has increased
• Weight rapidly lost due to
– Limited food intake
– Fat malabsorption
– Dumping syndrome
• Deficiencies of many nutrient stores
– Thiamine, Vitamins D, B12 and Folate
– Iron and calcium
Nutrition Care Post-Bariatric
Surgery and Pregnancy
• Nutrient deficiencies vary depending on type of
bariatric surgery performed
• Nutrition care includes:
– Assessment of dietary intake
– Supplement use
– Nutrient biomarker status
– Weight gain
– Physical activity
– Gastrointestinal symptoms
Diabetes in Pregnancy
• Diabetes: a leading complication in pregnancy
• Forms of diabetes include:
– Type 1 diabetes—Results from destruction of
insulin-producing cells of pancreas
– Type 2 diabetes—Due to body’s inability to use
insulin normally, or produce enough insulin
– Gestational—CHO intolerance with 1st onset
during pregnancy
Gestational Diabetes
• See in about 7.5% of pregnant women (and
increasing with obesity)
• Women who develop gestational diabetes
appear to be predisposed to insulin
resistance & type 2 diabetes
• Associated with increased levels of blood
glucose, triglycerides, fatty acids, & blood
pressure
Potential Consequences of
Gestational Diabetes
• Elevated glucose from mother – risk of adverse
outcomes.
– Spontaneous abortion, stillbirth, neonatal death
– Congenital anomalies
–  insulin   glucose uptake & triglyceride
formation in fetus
• Fetal changes  likelihood later in life:
– Insulin resistance and/or Type 2 diabetes
– High blood pressure
– Obesity
Adverse Outcomes Associated
with
Gestational Diabetes
Risk Factors for Gestational
Diabetes
• Linked to multiple inherited predisposition
• Environmental triggers such as:
– Excess body fat
– Low physical activity levels
Risk Factors for Gestational
Diabetes
Diagnosis of Gestational
Diabetes
• Glucose screening recommended for
women at high risk
• Risk factors are listed below:
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Marked obesity
Diabetes in a parent or sibling
History of glucose intolerance
Previous macrosomic infant
Current glucosuria
Glucose Screening
• First screen is a 50-g oral glucose challenge test
• If elevated, 3-hour, 100-g oral glucose tolerance
test (OGTT) is given
• Gestational diabetes diagnosed if ≥2 of the
following levels are exceeded:
– Overnight fast 95 mg/dL
– 1-hour after glucose load 180 mg/dL
– 2-hours after glucose load 155 mg/dL
– 3-hours after glucose load 140 mg/dL
Low Risk Women Not Needing
Glucose Screens
• Age <25 years
• Not Hispanic, African American, South or East
Asian, Pacific Islander, Native American, or
Indigenous Australian
• No diabetes in first-degree relatives
• Normal prepregnancy weight & normal weight
gain during pregnancy
• No history of glucose intolerance
• No prior obstetrical outcomes
Treatment of Gestational
Diabetes
• First approach is to normalize blood glucose
levels with diet & exercise
• If postprandial glucose remains high 2
weeks after adhering to diet & exercise,
insulin injections are added
• Medical nutrition therapy decreases risk of
adverse perinatal outcomes
Exercise Benefits &
Recommendations
• Regular aerobic exercise decreases insulin
resistance & blood glucose in gestational
diabetes
• Exercise should approximate 50-60% of
VO2 max, 3 times per week
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Nutritional Management of
Women with Gestational
Diabetes
Assess dietary & exercise habits
Develop individualized diet & exercise plan
Monitor weight gain
Interpret blood glucose & urinary ketone
results
• Ensure follow-up during & after pregnancy
THE DIET PLAN
• Whole-grain breads & cereals, vegetables,
fruits, & high-fiber foods
• Limited intake of simple sugars
• Low-GI foods, or carbohydrate foods that
do not greatly raise glucose levels
• Monounsaturated fats
• Three regular meals & snacks
Estimating Levels of Caloric
Need in Women with Gestational
Diabetes
• Distribute calories among 3 meals & several snacks
• Caloric levels & meal/snack plans are starting points
and my need modifications.
Consumption of Foods
with Low Glycemic Index
• Benefits of low-GI foods
has been debated and is
controversial
• Blood glucose response
with type 2 diabetes from
meals of white bread or
spaghetti is shown in
graph
• Note  Lower-GI
spaghetti improves blood
glucose levels
Menus for Women with
Gestational Diabetes
Other Topics on Diabetes in
Pregnancy
• Urinary Ketone Testing
– Monitored with dipsticks
• Postpartum Follow-Up
– 15% will remain glucose intolerant postpartum
– 10-15% will develop Type 2 diabetes in 2-5 yrs
• Prevention of Gestational Diabetes
– Reduce excessive weight and obesity
– Increase physical activity
– Decrease insulin resistance prior to pregnancy
Type 1 Diabetes during
Pregnancy
• Potentially, a more hazardous condition than most
cases of gestational diabetes
• Mother with type 1 is at risk of:
– Kidney disease
– Hypertension
– Other complications
• Newborn born to her is at risk of:
– Mortality
– Being SGA or LGA
– Hypoglycemia within 12 hours after birth
Nutritional Management of Type
1 Diabetes during Pregnancy
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Control of blood glucose levels
Nutritional adequacy of diet
Achieve recommended weight gain
Careful home monitoring of glucose levels
& dietary intake, exercise, insulin dose, &
urinary ketone levels
Multifetal Pregnancies
• U.S. rates of multifetal pregnancies have
increased
– Linked to assisted reproductive technologies
• Spontaneous multifetal pregnancy  after
35 years of age
• Incidence highest in women 45 to 54 y/o (1
in 5 are multifetal)
Background Information
About Multifetal Pregnancies
• Dizygotic
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2 eggs are fertilized
AKA Fraternal
~70% of twins
Different genetic
“fingerprints”
– Incidence increased by
perinatal nutrient
supplements
• Monozygotic
– 1 egg is fertilized
– AKA Identical
• (or almost identical)
– Always same sex
– ~30% of twins
– Rates appear not to be
influenced by heredity
Note the Differences in Placentas
and Amniotic Sacs
The Vanishing Twin Phenomeon
• It is estimated that 6 to 12% of pregnancies
begin as twins with only 3% born as twins
• Most fetal losses silently occur by
absorption into the uterus within the 1st 8
months
Risks Associated with Multifetal
Pregnancy
Complications Increase as
Number of Fetuses Increases
Nutrition and the Outcome of
Multifetal Pregnancy
• Weight gain in multifetal pregnancy
– IOM recommends 25-54 pounds
• Rate of weight gain in twin pregnancy
– 0.5 pounds per week in 1st trimester
– 1.5 pounds per week in 2nd & 3rd trimesters
• Weight gain in triplet pregnancy
– Gain of ~50 pounds or 1.5 pounds per week
Nutrition and the Outcome of
Multifetal Pregnancy
• Dietary intake in twin pregnancy
– Benefits from increases in essential fatty acids,
iron & calcium
• Vitamin and mineral supplements
– Needs unknown
• Nutritional recommendations
– Based on logical assumptions & theories
– Table 5.16 indicates “Best Practice”
HIV/AIDS during Pregnancy
• Treatment of HIV/AIDS
– Needed before, during & after pregnancy
• Consequences of HIV/AIDS during pregnancy
– Infection does not appear to be related to
adverse pregnancy outcome
• Nutritional factors and HIV/AIDS during
pregnancy
– Nutritional needs increase the most in advanced
stages of HIV/AIDS
Nutritional Management for
Women With HIV/AIDS during
Pregnancy
• Goals for nutritional management include:
– Maintenance of positive nitrogen balance & preservation of
lean muscle & bone mass
– Adequate intake of energy & nutrients to support maternal
physiological changes & fetal growth & development
– Correction of elements of poor nutritional status identified
by nutritional assessment
– Adoption of safe food-handling practices
– Delivery of a healthy newborn
Fetal Alcohol Spectrum
• “Fetal alcohol spectrum” describes range of
effects that fetal alcohol exposure has on mental
development & physical growth
• Effects include:
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Behavioral problems
Mental retardation
Aggressiveness
Nervousness & short attention span
Stunting growth & birth defects
Fetal Alcohol Spectrum
• Fetal exposure to alcohol is a leading
preventable cause of birth defects
– ~1 in 12 American pregnant women drink
alcohol
– 1 in 30 consume ≥5 drinks on 1 occasion at
least monthly
– 1 in 1000 newborns are affected by fetal
alcohol syndrome
Effects of Alcohol on Pregnancy
Outcome
• Alcohol easily crosses placenta to fetus
• Alcohol remains in fetal circulation because
fetus lacks enzymes to break down alcohol
• Alcohol exposure during critical periods of
growth & development can permanently
impair organ & tissue formation, growth,
health and mental development
Effects of Alcohol on
Pregnancy Outcome
• Heavy drinking (4-5 drinks/day) increases
risk of miscarriage, stillbirth, & infant death
• ~40% of fetuses born to women who drink
heavily will have fetal alcohol syndrome
• Because a “safe” dose of alcohol
consumption during pregnancy has not been
identified, it is recommended that women
do not drink alcohol while pregnant
Fetal Alcohol Syndrome
• First identified in 1973
• Characteristics
include:
– Anomalies of eyes,
nose, heart & CNS
– Growth retardation
– Small head
– Mental retardation
Nutrition and Adolescent
Pregnancy
• Growth during adolescent pregnancy
– Teen growth in height & weight at expense of
fetus
– Infants born to teens average 155g less than
those born to older adults
Nutrition and Adolescent
Pregnancy
Obesity, Excess Weight Gain and
Adolescent Pregnancy
• Overweight & obese adolescents are at
increased risk for:
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Cesarean delivery
Hypertensive disorders of pregnancy
Gestational diabetes
Delivery of excessively large infants
Dietary Recommendations for
Pregnant Adolescents
• Young adolescents may need more calories
to support their own growth as well as that
of fetus
• Caloric need should be from nutrient-dense
diet
• Calcium DRI for pregnant teens is 1300 mg
Nutritional Management of
Adolescent Pregnancy
• Multidisciplinary counseling services
should include:
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Individualized nutrition assessment
Intervention education
Guidance on weight gain
Follow-up birthweight outcomes
Nutritional Management of
Adolescent Pregnancy
• Services should focus on:
– Psychosocial needs
– Support/discussion groups
– Home visits
Evidence-Based Practice
“Enormous amounts of new knowledge are
barreling down the information highway,
but they are not arriving at the doorsteps of
our patients.”
− Claude Lenfant, National Institutes of Health