Placental metabolism

Question 1

What is the function of cytotrophoblasts?

Answer 1

cells from placenta that connect mother to fetus

Question 2

what are the functions of the placenta?

Answer 2

• transport
• synthesis of glycogen, lactate and cholesterol
• endocrine
• hormone catabolism
• nutrient storage
• protection against xenobiotics (limited)

Question 3

True or false

Fetal Hb has a greater capacity for oxygen binding

Answer 3

true

Question 4

Why glucose is transported through carrier mediated facilitated diffusion?

Answer 4

bc protein carriers can be saturated so there is a limit of glucose transfer from mother to fetus

Question 5

What is the consequence of malnutrition on placenta?

Answer 5

low Fe => reduced blood volume expansion => decreased cardiac outpout => decreased blood flow to placenta => decreased placenta size => reduced nutrient transfer => growth retardation

Question 6

What a deficiency in EFA can cause?

Answer 6

defects in placental integrity and function
DHA important in brain growth (highest amount present)
small head circumference + short gestation

Question 7

what is the role of progesterone during pregnancy?

Answer 7

• inhibits secretion of pituitary LH and FSH to prevent ovulation
• suppresses contractions of uterine smooth muscles

Question 8

What is the role of estrogen during pregnancy?

Answer 8

• supports myometrium growth and stimulates mammary gland development

Question 9

What is the role of human placental lactogen?

Answer 9

produced in late gestation

fat + CHO metabolism for fluel

Question 10

TRUE OR FALSE

During the third trimester the fetal weight more than doubles as well as the placenta

Answer 10

false placenta increases by only 50%

Question 11

What are physiological adjustments during pregnancy?

Answer 11

• increase GFR = excretion of fetal waste
• cardiac hypertrophy => increased cardiac output
• increased ventilation => oxygen demand
• increased plasma lipids => glu conservation
• decreased alanine availability => decreased muscle break down and increased placental uptake of alanine
• decreased GI motility => increased nutrient absorption

Question 12

What is the pattern of weight gain during pregnancy?

Answer 12

1st 10 weeks: 3-4 lbs
1lb/week for rest of pregnancy
> 29 BMI = limit weight gain of 6 kg

Question 13

What are the risks of excess weight gain during pregnancy?

Answer 13

preeclampsia = high blood pressure and organ damage => LBW and decreased blood flow to the placenta
edema, stillbirth

Question 14

What causes weight gain during pregnancy?

Answer 14

fetus growth
increase placenta & amniotic fluids
enlarged breast tissue and uterine 
increase in protein and fat stores
increase blood volume

Question 15

what are the most important determinants of birth weight?

Answer 15

• preconception weight
• maternal weight gain
• gestational age

Question 16

What is categorized as premature birth and what are the risks associated with it?

Answer 16

WHO: < 37 weeks
or 10th percentile for gestational age
- morbidity and mortality
- neurocognitive

Question 17

Go see slide 25

Answer 17

GO

Question 18

What are the risks of LBW?

Answer 18

1. decreased lung capacity
2. x2 CVD
3. x6 diabetes & impaired glucose metabolism
4. HTN, abnormal high TG, insulin and low HDL

Question 19

What is the risk of excessive birth weight?

Answer 19

increase in hormonally related cancers

Question 20

What is the metabolic mechanism to fight under-nutrition?

Answer 20

increase in glucocorticoids = increase in maturation of organs = better survival

Question 21

What are the categories for nutritional risks during pregnancy?

Answer 21

• low pre-weight and pregnancy weight
• adolescence
• short inter-conception interval
• chronic systemic illness
• dietary patterns
• history of anemia + obesity
• poverty
• reproductive history

Question 22

what happens during the last 4 weeks of pregnancy?

Answer 22

decline in nutrients transferred