Pregnancy

Question 1

Gestational age

Answer 1

Assessed from the date of conception

Average pregnancy is 38 weeks

Question 2

Menstrual age

Answer 2

Assessed from onset of last menstrual period
Average pregnancy is 40 weeks
40 weeks conceptualization includes 2 non-pregnant weeks

Question 3

Embryo-fetal development period

Answer 3

Week 1-2: implantation
Week 3-8: embryonic period
Week 9-38: fetal period

Question 4

Maternal body composition changes sequence

Answer 4

Maternal plasma volume
Maternal nutrient stores
Placental weight
Uterine blood flow
Fetal weight

Question 5

Maternal anabolic changes

Answer 5

Occur during first half of pregnancy
Ananbolic hormones: Insulin, GH, IGF, anabolic steroids

Blood volume expansion
Increased cardiac output
Build-up of fat, nutrient, and liver glycogen stores
Growth of some maternal organs
Increased appetite, food intake
Decreased exercise tolerance
Increased levels of anabolic hormones

Question 6

Maternal catabolic changes

Answer 6

Occurs in second half of pregnancy when most fetal growth occurs, catabolic changes make nutrients available to fetus
Catabolic hormones: Adrenaline, cortisol, Glucagon, epinephrine, noreprinephrine

Mobilization of fat and nutrient stores
Increased production and blood levels of glucose, triglycerides, fatty acids
Decreased liver glycogen stores- glycogenolysis
Accelerated fasting metabolism
Increased levels of catabolic hormones

Question 7

Fluid volume in pregnancy

Answer 7

Increases from ~7 L to 10 L
Increased blood volume
Increased body tissues
Increased extracellular volume
Amniotic fluid

Edema (in 60-75% of women)

Question 8

Hormonal changes in pregnancy

Answer 8

Human chorionic gonadotrophin (hCG)

Progesterone

Estrogen

Human chorionic somatotrophin (hCS)

1st trimester: Placenta secretes hCG, Ovaries secrete estrogen and progesterone
2nd trimester: Placenta secreates hCG, estrogen, progesterone, Ovaries secrete estrogen and progesterone
3rd trimester: Placenta alone secretes hCG, estrogen, and progesterone

Question 9

Human chorionic gonadotrophin (hCG)

Answer 9

• Stimulates production of estrogen and progesterone
• Stimulates growth of endometrium
• Secreted by placenta

Question 10

Progesterone

Answer 10

• Maintains the implant
• Stimulates growth of the endometrium and its nutrient secretion
• Stimulates breast development
• Promotes lipid deposition

Question 11

Estrogen

Answer 11

• Increases lipid formation and storage, protein synthesis, uterine blood flow
• Prompts uterine and breast duct development
• Promotes ligament flexibility

Question 12

Human Chorionic Somatotrophin (hCS)

Answer 12

• Increases insulin resistance (in order to maintain higher blood glucose levels for fetal use)
• Promotes protein synthesis
• Promotes fat breakdown for maternal energy

Question 13

Maternal nutrient metabolism

Answer 13

Accelerated fasting metabolism
Insulin resistance, altered blood glucose regulation
Reduced nitrogen excretion and conservation of amino acids
Accumulation of maternal fat stores, enhanced fat mobilization
Altered mineral metabolism

Question 14

Accelerated fasting metabolism

Answer 14

Increases in:
Glucogenic amino acid utilization
Fat oxidation, lipolysis
Production of ketones

During fasting, allows for:
Maternal use of stored fat
Sparing of glucose and amino acids for fetus

Question 15

Carbohydrate metabolism

Answer 15

Early pregnancy: High estrogen & progesterone stimulate insulin which increases glucose>glycogen & fat

Late pregnancy: Human chorionic somatotropin (hCS) & prolactin inhibit the conversion of glucose to glycogen & fat

Diabetogenic effect of pregnancy:
Mother goes into transient insulin resistance during pregnancy in order to keep blood sugars higher for the fetus which is the preferred fuel

Question 16

Protein metabolism

Answer 16

• Aim to ensure nitrogen conservation for fetal growth during the last quarter of pregnancy
• Decreases in nitrogen excretion in later pregnancy
• Conservation of amino acids for tissue synthesis
• Protein is not stored during early gestation for later use
• Increased protein needs must be met by physiological adjustments that enhance dietary protein utilization

Question 17

Fat metabolism

Answer 17

Fat stores:

• Accumulate in first half of pregnancy
• Enhanced fat mobilization in last half, fat stores broken down (lipolysis)

Blood lipid levels increase
Increased cholesterol is substrate for steroid hormone synthesis

Question 18

Mineral metabolism

Answer 18

Calcium
-Increased bone turnover & reformation

Sodium

• Accumulation in mother, placenta, & fetus
• Restriction of sodium potentially harmful

Question 19

Functions of the placenta

Answer 19

Hormone and enzyme production
Nutrient and gas exchange
Removal of waste from fetus

Nutrient Transfer Priorities:

1. Maternal needs
2. Placental needs
3. Fetal needs

Question 20

Newborn weight

Answer 20

Determined by:

• Energy, nutrient & oxygen availability
• Genetics
• Insulin-like growth factor (IGF-1)

Weight classifications:

• Normal = 5lb 8 oz- 9lb, 4oz
• LBW: Low Birth Weight (< 5 lbs 8 oz)
• VLBW: Very Low Birth Weigh (< 3 lbs 4 oz)
• SGA: small for gestational age (<10th percentile)
• LGA: large for gestational age (>90th percentile)

Question 21

Weight gain in pregnancy

Answer 21

• Low weight gain during first trimester (~5 lbs)
• Gain of a little less than 1 lb per week for the 2nd and 3rd trimesters
• No weight loss is recommended, even in obese

Fetus is only ~1/3 of weight, the remainder is a combination of:

• breast tissue
• fluid volume
• placenta
• uterus and supporting muscles
• amniotic fluid
• fat stores

Question 22

Postpartum weight loss

Answer 22

~15lbs lost at delivery

Lactation reset hypothesis

Question 23

Prenatal energy and nutrient needs

Answer 23

Caloric needs:
-1st trimester: little to no increase
-2nd trimester: ~340 kcal/day
-3rd trimester: ~450 kcal/day
Protein needs: 
-Increase by 25 grams/day (71g/day)
Fat needs:
-Slightly increased needs for essential fatty acids, DHA and EPA, n-6
Fiber needs: 
-Increases from 25 to 28 grams/day

Question 24

Folate

Answer 24

Deficiency leads to:
Impaired DNA synthesis, gene expression, gene regulation
Leads to abnormal cell division and tissue formation

Accumulation of homocysteine (a metabolite) and shortage of methionine may cause placenta rupture, stillbirth, preterm labor, preeclampsia, structural abnormalities
(Methionine gets converted to homocysteine, when levels of homocysteine are too high in the body, will convert back to methionine with the use of B12 and folate. If not enough folate, build-up of homocysteine)

Question 25

Choline

Answer 25

Component of phospholipids in cell membranes Precursor of intracellular messengers Source of methyl groups needed for DNA regulation, brain development

Question 26

Vitamin A

Answer 26

Involved in cell differentiation Deficiency is rare, excess is a concern (medications: Accutane, Retin-A) Teratogenic

Question 27

Iron

Answer 27

+1000mg additional iron needed during pregnancy (over all of pregnancy, not per day) 300 mg for fetus and placenta 250 mg lost at delivery 450 mg to increase RBC mass 12% of women enter pregnancy with iron deficiency Increased risk for preterm delivery and LBW Impaired cognitive development in offspring Low iron during pregnancy = newborn with low iron stores

Question 28

Hypertension

Answer 28

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 HTN in pregnancy is related to: Chronic inflammation Oxidative stress Damage to the endothelium of blood vessels Consequences of endothelial dysfunction: Impaired blood flow Increased tendency to clot Plaque formation

Question 29

Chronic Hypertension

Answer 29

HTN present before pregnancy or diagnosed <20 weeks More common in: African American, obese, >35 years of age, or history of HTN with previous pregnancy Associated with increased risk of: preterm delivery, fetal growth retardation, placenta abruption, Cesarean delivery

Question 30

Gestational Hypertension

Answer 30

Hypertension diagnosed for first time after mid-pregnancy No proteinuria Tend to be overweight or obese with excess central body fat

Question 31

Recommendations for Hypertension

Answer 31

Intervention should aim to achieve adequate & balanced diets for pregnancy Weight gain is same as for other pregnant women Continue Na reduction required for blood pressure control without too little that could impair fetal growth

Question 32

Preeclampsia-Eclampsia

Answer 32

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 Oxidative stress, inflammation, & endothelial dysfunction Platelet aggregation & blood coagulation due to deficits in prostacyclin relative to thromboxane Blood vessel spasms & constriction Increased blood pressure Insulin resistance Adverse maternal immune system responses to the placenta Elevated blood levels of triglycerides, free fatty acids and cholesterol

Question 33

Recommendations for Preeclampsia-Eclampsia

Answer 33

``` Adequate calcium intake Adequate vitamin D status Use of multi-vitamin/minerals if needed >5 servings of colorful vegetables and fruits daily Adequate fiber intake (>21 grams/day) Basic foods from MyPlate recommendations Moderate exercise Recommended weight gain ```

Question 34

Obesity

Answer 34

Obesity increases risk for: - Stillbirth - LGA - Cesarean section - Offspring overweight and type II diabetes

Question 35

Recommendations for Obesity

Answer 35

``` Meet nutrient needs Consume a variety of basic foods Participate in physical activity Maintain appropriate rates of weight gain Weight loss is not recommended ```

Question 36

Gestational Diabetes

Answer 36

Women developing gestational diabetes appear to be predisposed to insulin resistance, and have impaired insulin production Related to metabolic changes favoring oxidative stress and elevated blood glucose Elevated glucose from mother – risk of adverse outcomes. - Spontaneous abortion, stillbirth, neonatal death - Congenital anomalies - Glucose uptake & triglyceride formation in fetus Fetal changes increase likelihood later in life: - Insulin resistance and/or Type 2 diabetes - High blood pressure - Obesity

Question 37

Recommendations for Gestational Diabetes

Answer 37

First approach is medical nutrition therapy to normalize blood glucose levels with diet & exercise Blood glucose levels can be brought down with low calorie intake – avoid elevated ketones Oral medication metformin (glyburide) used to decrease insulin resistance Regular aerobic exercise Assess dietary & exercise habits Develop individualized diet & exercise plan Monitor weight gain Interpret blood glucose & urinary ketone results Ensure follow-up during & after pregnancy

Question 38

Fetal Alcohol Spectrum Disorders (FASD)

Answer 38

Alcohol-related neurodevelopment disorder (ARND) - No overt physical features - Intellectual disabilities - Problems with behavior, learning, coping, impulse control, attention Alcohol-related birth defects (ARBD) -Abnormalities of the heart, kidneys, bones, or hearing Fetal alcohol syndrome (FAS) - Most severe form - Abnormal facial features - Growth problems - CNS abnormalities - Problems with social skills, learning, memory, attention span, communication, vision, hearing