Pre-pregnancy and pregnancy Flashcards
Who is the man behind the systematic reviews of all relevant RCTs of health care?
Archie Cochrane
In pre-pregnancy, why is body fat important
body fat is an important source of oestrogen required for egg maturation
- influences oestrogen metabolism
Define fertility:
capacity of a women to produce normal ovum periodically and of a man to produce normal sperm, the ability to reproduce
Define conception:
the union of male sperm and female ovum; fertilisation
define placenta:
organ that develops inside uterus in early pregnancy, through which the foetus receives nutrients and oxygen and returns carbon dioxide and other waste products to be excreted
What habits must a women establish prior to pregnancy?
- Maintain healthy body weight
- Adequate/balanced diet
- Be physically active
- Manage chronic conditions
- Avoid harmful influences
In terms of body weight prior to pregnancy, what happens in excess or low body fat?
excess = disrupts menstrual regularity and ovarian hormone productions
low = higher pituitary hormone control over ovulation
In terms of body weight prior to pregnancy, what happens if the men are overweight/obese?
low sperm counts, hormonal changes would reduce fertility
What happens once the visceral hindbrain detects info regarding fuel availability?
sends indirect and direct projections to regions of forebrain playing important roles in regulation of energy balance + reproductive function
What results from ingestion of harmful substances prior to pregnancy?
- cause abnormalities
- alter gene expression
- interfere with fertility
Why is there an issue of high retinol intake?
intake during first trimester of pregnancy, there’s higher incidence of babies with birth defects. teratogenic effects
What are the advises given to pre-conceptual/pregnant women regarding intakes?
- no supplements containing retinol
- don’t eat liver (100g liver)
- carotene-containing foods allowed freely
What are the effects of zinc deficiency prior to pregnancy?
- congenital/foetal malformations
- linked with sperm viability
- contraceptive pill decreases circulating zinc (and folate, Vit. B6)
Can infection and inflammation decrease plasma zinc?
yes
What are the key structures developed in early pregnancy?
- Placenta in uterus
- Amniotic sac
- Umbilical cord
What is the amniotic sac?
fluid-filled ballon-like structure, houses the fetus
What is the umbilical cord?
rope-like structure containing fetal blood vessels that extends through fetus’ belly button (aka umbilicus) to placenta
What is the placenta?
- metabolically active (by 10th week of gestation)
- interwoven maternal and foetal blood vessels
- exchange nutrients, oxygen, waste products
What general functions does the placenta perform?
- respiratory
- absorptive
- excretory
What are the steps from zygote to a new born infant?
- Newly fertilised ovum, zygote. Cells rapidly divide in less than a week, ready for implantation
- Placenta develops, provide nutrient for embryo 5 weeks after fertilisation
- Fetus is just over an inch long, 11 weeks after development
- Newborn infant after 9 months, 20 times longer, 50 times heavier
What happens in weeks 0 to 8?
fertilised egg moves slowly along fallopian tube after 3 weeks, towards womb for development of major organs
What happens from weeks 9 to 12?
- formation
- the heart fully forms
- bones harden but skull bones stay soft
How many beats per minute is the fetus heart rate at around 9-12 weeks?
180 beats/min
Why do the skull bones stay soft around 9-12 weeks?
separated to make the journey through birth canal easier
When are the critical periods of the fetal development?
during the early period and rapid cell division
- cellular activities can occur only at these times
What happens if cell division and number are limited during critical period
full recovery not possible
What does the neural tube structure eventual become?
brain and spinal cord
What days of gestation is the critical period for neural tube development?
17 to 30 days
What are the types of neural tube defects?
- Anencephaly
- Encephalocele
- Spina bifida
- Damage to nerves and muscles
What is anencephaly?
- brain missing or fails to develop
- pregnancies affected often end in miscarriage
- infants born die shortly after death
What is encephalocele?
protrusion of the brain
what is spina bifida?
incomplete closure of the spinal cord and bony encasement
What might be the cause of neural tube defects (NTDs)?
diet (folic acid supplementation would prevent NTDs)
What factors make NTDs more likely?
- previous pregnancy affected by NTD
- maternal diabetes (type 1) OR obesity
- maternal use of antiseizure medications
- exposure to high temperatures early in pregnancy
- race/ethnicity (more common among whites/Hispanics)
- low socioeconomic status
How much folate supplementation is recommended daily?
0.4g
If a women had an infant with NTD, what is the recommended intake daily?
5mg/day (10x larger)
High doses of folate might mask symptoms of?
pernicious anaemia of vit. B12 deficiency (so anything about 1mg folate requires B12 prescription)
What happens from weeks 13 to 16?
honeymoon period
- ovaries or testes fully developed inside body
- foetus starts to hear, body grows (85mm, 25g)
What happens from weeks 17 to 20?
skin development, nervous system
- movement starts
- 150g
What happens from weeks 21 to 24?
foetus has chance of survival if born
- 350g
What happens from weeks 25 to 28?
foetus has chance of survival if born
- follow pattern for waking and sleeping (diff. pattern from mother)
What happens from weeks 29 to 32?
foetus very active
- suckling reflex
- brain and nervous system developing
- extra weight starts accumulating
- breathless feeling
- leg cramps
- difficulty sleeping
- “Braxton Hicks” contractions
What happens from weeks 33 to 36?
brain and nervous system full developed
- bones harden (skull bone stays soft)
- digestive system ready, lungs fully formed
- mother = tiredness, backaches, sleeplessness
What percentage of babies arrive on their due date?
5%
What happens from weeks 37 to 40?
37 weeks is the full-term pregnancy
- amniotic fluid turns into waste, meconium, in babies intestines
- baby is ready to be born
How much does the BMR increase in 2nd half of pregnancy %?
15%
What influences infant birthweight?
- mother’s weight prior to conception
- weight gain during pregnancy
What happens to the baby if mother is underweight prior to conception?
- high risk of low infant birthweight
- rates of preterm births/infant deaths are higher
What happens to the baby if mother is overweight/obese prior to conception?
- high risk medical complications
- preeclampsia, gestational diabetes etc)
- labour and delivery complications (post-term caesarean section, birth trauma)
Is weight-loss dieting during pregnancy advisable?
No, never
What is the estimated weight gained during pregnancy?
13.6kg OR 30 lbs
What passes through the placenta to the foetus?
glucose, amino acids, FFA, ketones
What doesn’t pass through the placenta to the foetus?
insulin, glucagon
What is the rate at which foetus uses glucose?
6mg/kg/min at term
What is an important precursor of glucose in gluconeogenesis of the foetus?
maternal hypoaminoacidemia
What are the changes in the body physiology of GI system of the mother during pregnancy?
- motility slowed down, muscle walls relax
- gastric acid secretion reduced
- foetus is pushing mother’s stomach
What is the advantage of GI muscle walls relaxing?
- increases time available for digestion
- maximises absorption of nutrients
What is the advantage of GI reduced acid secretion?
may improve absorption of Ca and Fe
What is the results of foetus is pushing mother’s stomach?
causes reflux of gastric contents into oesophagus
What is the dietary advice given to mothers since there are all these GI changes?
- small frequent meals
- milk/yoghurt relieves symptoms
- avoid spicy, fatty foods, citrus fruit
- no unripe bananas and fizzy drinks
How much blood is required from the mom for a full term placenta?
625ml
What does cardiomyocytes increase and decrease in cardiac metabolism of the baby?
increase utilisation of fatty acids
decreases glucose utilisation
How much increase is there in plasma volume of CV system during the physiology changes of pregnancy?
1250-1500ml
how much increase in red cell mass is there during the physiology changes of pregnancy?
240ml
What are the changes in physiology of pulmonary system during pregnancy?
- O2 demand!!
- O2 consumption increases 25%
- progesterone will increase sensitivity of chemoreceptors to CO2
- pCO2 decrease to increase placental-maternal CO2 transfer
- pressure on diaphragm from uterus
What are the changes in physiology of urinary system during pregnancy?
- aldosterone expands plasma volume, more water/salt retention @ kidneys
- increased kidney size/glomerular filtration rate
- urine output elevated
- pregnant uterus compresses bladder + reduce capacity = frequent urination
- progesterone-induced muscle hypotonia (incontinence)
What are some complications of pregnancy on the mother?-
- mild to annoying discomforts, sometimes life-threatening illnesses
- maternal morbidity
- hyperemesis gravidarum
- anaemia
- gestational diabetes
- pre-eclampsia
What increases the burden in complications of pregnancy?
- increase in maternal age
- pre-pregnancy obesity
- pre-existing chronic medical conditions
What is hyperemesis gravidarum?
severe, persistent nausea and vomiting during pregnancy which may require intensive treatment
How many women are possibly affected?
2%
What is involved in the hyperemesis gravidarum in 1st trimester?
placenta and human chorionic gonadotrophin (HCG) hormone, it’s associated with nausea or vomiting
What are the symptoms and results of hyperemesis gravidarum?
- ketonuria
- dehydration
- fluid-electrolyte imbalance (hypokalaemia)
- nutritional deficiencies
- weight loss
What diet is recommended for hyperemesis gravidarum?
- dry diet (bread, pasta, rice, porridge, bananas)
- fluid in small quantities, 30mins after meal
- litter protein added slowly
- avoid spicy food, strong smells
What do pregnant women with anaemia feel like?
weak, tired
What happens in gestational diabetes?
- hyperglycaemia occur temporarily
- increase in production of hormonal anatagonists to insulin
- failing pancreas, can’t meet demands
- insulin needed in last trimester
- lead to large babies, difficult labours
- greater childhood obesity risk, and insulin resistance
What are the risk factors of gestational diabetes?
- age >25yo
- BMI >25
- previous pregnancy complications
- family history of diabetes
- hispanic, black, native american, south/east asian, pacific islander, indigenous australian
What is pre-eclampsia?
hypertension, proteinuria, edema, happens in 3rd trimester
- decreased uterine blood flow, reducing fetal nourishment
What are the risk factors of pre-eclampsia?
first pregnancy OR protein/Ca deficiency
Who are the vulnerable groups for pre-eclampsia?
- adolescent mothers
- immigrant women, consume inadequate diet
- vegans/vegetarians
- women with limited budgets
- parents with alcohol or drug problems
- women with bizarre, restricted diets
What is SACN?
Scientific advisory committee on nutrition
What is the dietary advice by SACN regarding fish?
- 2 portions of fish (one oily fish)
- avoid marlin, swordfish, shark, lesser extent tuna (due to methyl-mercury contamination)
What amount of fish for maternal intake would be harmful to foetus?
> 3.3μg/kg body weight mm per week
What is the dietary requirement of vit. D to prevent rickets in the baby?
10mcg/day
What are fatty acids are essential for normal development esp. neutral tube?
- arachidonic acid (AA)
- docosahexaenoic acid (DHA)
What increases breast milk ALNA and EPA (not DHA)?
consumption of α-linolenic acid (ALNA)
Recommendations during lactation:
- Balanced diet - high proportions of nutrient-dense foods
- No reducing diets
- Moderate exercise
- High fluid intake (6-8 drinks/day)
- Limited caffeine and spicy foods
- No smoking and avoid alcohol
What are the benefits of prolonging pospartum amenorrhoea?
- assist in maintenance of maternal Fe status
- assist maternal weight loss, not consistent though
What are the risks of prolonging pospartum amenorrhoea?
- obesity, changes in eating patterns
- risk of osteoporosis
What mineral is drained from pregnancy and lactation?
Ca2+
How can the drained Ca2+ demand be met during pregnancy and lactation?
- increased Ca in diet (DRV + 550mg/day)
- increased efficiency of Ca absorption
- conservation of renal Ca
- increased bone Ca2+ mobilisation with net loss of bone
Is the macronutrient content of milk from well-nourished and undernourished women very similar?
Yes
Is it true that fat soluble vitamins and minerals are less responsive due to buffering effects of maternal stores and carrier proteins?
True.
What are the symptoms of postpartum depression?
- low mood, last > 2 weeks
- struggle to look after self and baby
- simple tasks difficult to manage
- feel distressed, guilty
- PND starts within 1-2 months of giving birth
What does the foetal alcohol syndrome (FAS) include?
poor growth and learning/behavioural difficulties
