nutrition in pregnancy, lactation, infancy, and childhood

zygote path

• zygote= fertilized egg

• travels through fallopian tube to uterus where it implants into uterine lining

• implantation complete after about 14 days

embryonic stage of development

• 2-8 weeks

• cells of embryo begin to differentiate, arrange themselves and begin organ development

fetal stage of development

• 9 weeks until birth

• fetus continues to grow

• develops internal and external organ structures

• length is approximately equal to weeks gestation

fertilization location and timing

• in oviduct

• 12-24 hours after ovulation

when does egg compete first cell division

after about 30 hours

becomes 100 cells after about 3-4 days

where does nutrient and waste transfer occur

placenta

placenta

• organ that develops during pregnancy to facilitate transfer of nutrients to the growing fetus and the removal of waste products

• made of maternal and fetal tissue

• maternal and fetal blood supply do NOT mix

  • brings blood close enough to allow for nutrient transfer

• releases hormones that are needed to maintain pregnancy

why does maternal body change

to support pregnancy, fetal development, birth, and lactation

weight gain during pregnancy

• purpose: fetal growth and development, additional energy stores

how much weight is gained during pregnancy and what makes up this number

• 11.5-16 kg

how much weight is lost immediately after giving birth

• around 5 kg (10 lbs)

• fetus and amniotic fluid

how much weight should be gained during pregnancy based on pre pregnancy BMI

overall: the heavier pre gestation, the less weight to gain so if underweight before pregnancy, need to gain more weight

*memorize these numbers

what happens if you gain too little weight

• low birth weight or pre term birth

• increases in child’s risk of heart disease or diabetes later in life

what happens if you gain too much weight

• high BP

• diabetes

• difficult delivery: C-section

• infants large for gestational age

correlation between weight gain and size of infant when born

hypertensive disorders of pregnancy stats

• 5-10% of pregnant person experience high BP during pregnancy

• 30% are related to -re-existing chronic HTN

gestational HTN

• abnormal rise in BP that occurs after 20th week of pregnancy

• may be a signal of a more serious condition (preeclampsia: high BP and loss of protein in urine → organ damage)

spiral uterine artery changes in pregnancy

• non pregnant: longer and more spiraling

• normal pregnancy:

  • runs in spiral shape within functional layer

  • forms capillary network and blood sinuses when it reaches the superficial layer of the functional layer

  • then merges into small veins and merges through muscular layer to form uterine artery

• pre-eclampsia

  • spiral artery recasting disorder: shallow implantation of placenta vessels

gestational diabetes mellitus

• consistently elevated glucose level during pregnancy in a person without previously diagnosed DM

• in 3-20% of all pregnancies

who is at higher risk of GDM

• obese

• family hx of T2DM

what are the long term consequences of GDM

increased risk for T2DM later in life

patho of GDM

• risk factors: obesity, inflammatory cytokines

• results in excessive peripheral insulin resistance and insufficient insulin production

• excessive endogenous glucose production, excessive peripheral insulin resistance

• also caused be placental related hormones

• results in increased glucose production decreased uptake, resulting in hyperglycemia

epigenetics of GDM and offspring health: the time for action is in early stages of life article → what are the key highlights

• intrauterine hyperglycemia is not only associated with increased perinatal morbidity and mortality, but also with increased lifelong risks of the exposed offspring for obesity, metabolic, CV and malignant disease

• fetal overnutrition (and undernutrition) lead to persistent epigenetic changes in developmentally important genes, influencing neuroendocrine functions, energy homeostasis and metabolism

what are vital nutrients during pregnancy

• zinc

  • rapid growth and enzymes

• iron

  • blood vessels, avoid anemia

• folate

  • neural tube development

  • neural tube closure done by day 28

how much extra energy is needed during different trimesters and lactation

• 1st trimester

  • 0 kcal/day

• 2nd trimester

  • 350 kcal/day

• 3rd trimester

  • 450 kcal/day

• lactation

  • 300-400 kcal/day

nutrition needs during pregnancy and lactation

pregnancy:

• protein

• folate

• IRON

• zinc

• iodine

• B6

lactation:

• protein

• vitamin A, E, C

• B6

• iodine

• selenium

maternal factors risk for mother and infant/fetus

maternal factors risk for mother and infant/fetus pt. 2

why does a pregnant adolescent need different nutrient requirements

• adolescent girls continue to grow and mature physically for about 4-7 years after menstruation begins

• diet of pregnant teen must provide both for her growth and that is baby

pregnant adolescent nutrient requirements

• niacin

• B6

• iron

• copper

teratogens

substances of chemical or biological origin that can cause birth defects

critical periods

time when different organ systems are particularly susceptible at different times

when are most critical periods

embryonic development (3-8 weeks)

Canadian Prenatal Nutrition Program (CPNP)

• provides funding to community groups to hep to improve the health of pregnant women, new mothers, and their babies who face challenges that put their health at risk such as;

  • poverty

  • teen pregnancy

  • social and geographic isolation

  • substance use

  • family violence

lactation

involved the synthesis of milk components, including protein, lactose adn lipids, and the movement of the milk through the milk ducts to the nipple

let-down

• the release of milk from the glands through the ducts

• triggered by the hormone oxytocin

colostrum

• immature milk

• secreted during first days after delivery

• rich in protein and immune factors

iron needs during lactation

• decrease by ½

• because not menstruating

do lactating individual need more fluid

yes- not certain amount though just in general

where does energy come from for lactation

fat stores created during pregnancy

infant nutritional needs

• higher percent of fats than adults

• almost double amount of protein relative to adult

• water intake is critical (high surface area: volume ratio)

most common cause of infant mortality

dehydration due to diarrhea

breastmilk nutrition

• includes most nutrients needed for infant growth except vitamin D and K

• poor source of iron

• fluoride supplementation recommended at 6 months in breast fed infants

infants following vegan diet

may need B12 supplementation

infant iron supplementation

• iron rich foods needed at 6 months

• after 6 months iron stores are depleted

health canada breast feeding recommendations

• exclusive breastfeeding for first 6 months

• sustained for up to 2 years or longer with appropriate complementary feeding to support nutrition needs

benefits of breastfeeding

• nutrients and protection

  • perfect amount of nutrition and antibodies for disease prevention

• brain power

  • higher IQ

• convenient and portable

  • breast milk always safe, fresh, exactly right temp

• size does not matter

  • breast will produce enough milk for baby regardless of size

• benefits mothers too

  • helps lose weight and reduce risk of some cancers

• continues the special relationship

  • helps with bonding

• benefits don’t stop

  • all additional time continues to help more in child

• easy on budget

  • no buying formula

• works for working mothers

  • can be expressed with pump so that others can help with feedings

• good for environment

  • no waste, pollution, packaging

who is most likely to breastfeed for first 6 months

those who:

• have partners

• do not smoke during pregnancy

• deliver in their home

• do not work

formula composition regulation

Canadian Food and Drug Regulations and enforced by Canadian Food Inspection Agency

growth

• measurable change in body size due to 2 underlying cellular processes

  • hyperplasia: increase in cell number

  • hypertrophy: increase in cell size

  • accretion: increase in intercellular substances

what do growth charts identify

malnutrition

• undernutrition (weight for age)

• stunting (length for age)

• wasting (weight for length, BMI for age)

• overnutrition (weight for length, BMI for age)

how is children’s growth compared

• compared to growth charts of average growth during checkups

  • 99th percentile: larger (higher BMI) than 99% of other children= very large for age

  • 50th percentile: larger than 50% of other children

  • 3rd percentile: larger than 3% of other children (= very small for age, “abnormal”)

when is BMI used

after 2 years of age to account for body changes due to puberty

birth to 6 months developmental milestones and foods

milestones:

• takes milk by sucking

• solid food placed in mouth usually pushed out because tongue is thrust forward during sucking

• by 6 months tongue action diminished that baby can accept solid food

foods

• exclusively breast milk

• infant formula if breastfeeding is not possible

• vitamin D supplement if breastfed

6-12 months developmental milestones and foods

milestones

• infant can hold head up, sit, chew, hold food, move hand to mouth

• progresses to drinking from cup and feeding self

foods

• breast milk or formula (cows milk after 9 months)

• iron-fortified infant cereal

• pureed or drained vegetables

• fruits

• finger foods like cooked pasta or cooked and cut vegetables

12-18 months developmental milestones and foods

milestones

• feed self

• drink from cup, use spoon, bite food well, eat ground or chopped table food

foods

• breast milk or cow’s milk

• meats and beans

• iron-fortified cereal

• chopped veg

• soft fruit

• finger foods

• move towards following Canada’s food guide

nutrition and health concerns in children

• dental cavities

• food allergies

• diet and hyperactivity

  • evidence is mixed and weak overall

• childhood obesity

  • impact of screen time

  • advertising (ex. sat morning cartoon ads favour unhealthy food cereal, snacks, candy..)

food allergy

• more common in infants than adults

• exposure to allergen for first time causes immune system to produce antibodies to that allergen

allergy symptoms

• sneezing, rash, eczema, hives, cramps, aches, vomiting, asthma, diarrhea

• may be immediate or take up to 24 hours to appear

• may range from mild to life-threatening

food intolerances

• do NOT cause antibody production

• create problems during DIGESTION

• ex. lactose intolerance

top 8 food allergens

• milk

• eggs

• fish

• shellfish

• peanuts

• tree nuts

• wheat

• soy

*must be indicated on food labels

5-4-3-2-1 GO! initiative

• 5 servicing of fruit and veg per day

• 4 serving of water per day

• 3 servings of low fat dairy a day

• 2 hours or less of screen time per day

• 1 hour or more of physical activity per day

• 0 sugar sweetened beverages

*to combat obesity