Nutrition Through the Life Cycle - Pregnancy Flashcards
When is preconception and periconception?
Preconception = 3 months before conception Periconception = 2-3 months before and after conception
What weeks entail the 1st, 2nd and 3rd trimester?
1st = 0 - 12 weeks 2nd = 13 - 26 weeks 3rd = 27 - 40 weeks
What are some steps both women and men can take preconception?
- Both can check fertility and do what they can to improve fertility (high adiposity = leptin decrease in women = reproductive cycling issues)
- Stop smoking and excess caffeine use
- Ensure stores of folic acid, zinc are optimal
What the 3 stages of foetal growth?
Blastogenic stage - <2 weeks
Embryonic stage - 3-8 weeks
Foetal stage >9 weeks
What is the purpose of the placenta?
- Gaseous exchange
- Nutrient exchange
- Waste removal
- Hormone and enzyme production
What changes occur for the embryo and mother in the first trimester (>=12 weeks)?
Embryo:
- Implants into uterine lining
- Establishes to placenta
- Organogenesis
Mother:
- Placenta formation
- Hormonal changes
What changes occur for the embryo in the second trimester (13 - 26 weeks)?
- Development into foetus
- Massively increased mass (25-875g)
What changes occur for the foetus in the third trimester (27 - 40 weeks)?
- Foetal maturity
- Increased body size (x4)
- Maturation of organ systems
- Deposition of nutrient and fat stores
What are some physiological demands of the mother during pregnancy?
- Hormonal changes
- Tissue changes (breast)
- Increased blood volume
- Uterus expands
- Increased fat stores
What 2 hormones increase dramatically during pregnancy? What do both of these hormones do?
Estrogen:
- Increases lipid formation/storage
- Increased uterine blood flow
- Prompts breast duct development
- Stimulates angio-tensin system
- Sodium retention
Progesterone:
- Stimulates endometrium growth
- Stimulates maternal fat
- Increases sodium excretion
What is leptins function in preganancy?
- Regulation of appetite
- Lipid metabolism
- Utilisation of fat stores
What is the ideal birthweight for a baby?
3.1 - 3.6kg
What is the ideal total weight gain in the first trimester for each BMI?
0.5 - 2kg for all BMIs
What is the ideal total weight gain in the 2nd & 3rd trimester for each BMI?
<18.5 = 0.51 kg/week
18.5 - 24.9 = 0.42 kg/week
25.0 - 29.9 = 0.28 kg/week
> 30.0 = 0.22 kg/week
gradual 0.2-0.5 kg/week depending on initial BMI
Roughly how many calories does pregnancy cost a woman?
85,000 kcal
What associated risks are there for pre-pregnancy overweight women?
- Gestational diabetes
- Hypertension
What does the ‘Barker hypothesis’ propose?
Low birth weight (<2500g) = increased risk of CVD, hypertension, type II diabetes later in life
Pregnancy involves huge metabolic changes and growth of maternal tissue imcreasing nutritional demands dramatically. What adaptations take place to combat this?
- Increased bioavailability
- Increased optimisation of nutrients
How many kcal/day should a pregnancy woman consume and when?
Additional 200kcal/day in 3rd trimester from nutrient dense foods
*EAR from Dep of Health (UK)
How much additional protein should a pregnant woman consume?
RNI = 6g/day
*Dep of Health
How much additional folic acid should a pregnant woman consume?
What is folic acid required for during pregnancy?
What foods are high in folic acid?
Pre-conception = +400µg/day (supplementation)
During Pregnancy = +300µg/day (dietary)
- Prevent NTDs
- Cell division
- Maintenance of normal RBCs
- Citrus fruits, dark green leafy vegetables, fortified foods, eggs, grains.
Folic acid fortification is mandatory in the UK. In which food? How many NTD cases are prevented from this mandatory fortification?
White flour.
700-900 cases/year
How much additional iron should a pregnant woman consume?
What is iron required for during pregnancy?
What does iron deficianecy anemia increase the risk of?
What foods are high in iron?
None if not deficient.
Supplementation if stores are not optimal.
RNI = 14.8mg/day
Requirements:
Foetus - 400mg
Placenta - 175mg
Maternal RBC formation - 430-1000mg
Deficiency increases risk of preterm delivery, low infant birthweight, poor infant iron status
Foods: red meat, fortified foods.
How much additional calcium and vit D should a pregnant woman consume?
What is calcium and vit D required for during pregnancy?
What foods are high in calcium and/or vit D?
Ca = no increase. 700mg/day
Vit D = 10 µg/day (supplement)
Requirements:
- Foetus bone formation
Foods: Milk, fortified foods, dark leafy greens
How much additional vit A should a pregnant woman consume?
RNI: +100µg/day (700µg/day)
Is caffiene safe during pregnancy?
Risks of too much caffiene?
<200mg caffiene is safe (equivalent to 1 cup)
Risks:
- Diffuses into infants blood straight from mother
- Decreased infant growth
- Develoment problems
Is smoking safe during pregnancy?
Risks of smoking?
No.
Risks:
- limits nutrient and oxygen delievery to foetus
- LBW babies
- Increased miscarriage risk
- Preterm delivery
- Depletes vit C stores
Is alcohol safe during pregnancy?
Risks of drinking alcohol?
Not necessarily.
Risks:
- Birth defects
- Mental retardation
- Slow development
- Foetal Alcohol Spectrum Disorders (FASD)
- LBW
- Preterm delivery
Are non-nutritional sweetners safe during pregnancy?
Risks of drinking NNSs?
Depends on the NNS.
Some are relitively safe, others reccomended to avoid.
E.g.
sucralose & stevia = safe
aspartame = safe in moderation
saccharin = recommended to avoid however deemed safe in UK
Foods to avoid during pregnancy?
- Raw fish/seafood
- <2 portions oily fish/week
- Soft/blue cheeses
- Raw meat
- Unpasturised milk
What are some common dietary problems reported by pregnant women?
- Nausea/vomiting (7/10 pregnancies)
- Heartburn (30-50% pregnancies)
- Constipation
What are some prgnancy related conditions?
- Preeclampsia (high blood pressure and fluid retention)
- Gestational Diabetes
