pregnancy and perinatal health Flashcards
contraception
used to help avoid pregnancy
conception
look for time in cycle when ovulation happens before and therefore pregnancy more likely
more often due to chance
possible fertility issues
7
social and environmental factors
- Age
- Smoking
- BMI
- Exercise
- Drugs
- Folate
- Alcohol
folate and fertilisation
folic acid become increasingly recognised for a normal successful pregnancy
- neural tube defects e.g. Spina Bifida
- more likely to happen if folate is low – should take supplements
alcohol and fertiliry
neurological and developmental changes
- foetal alcohol syndrome (very early into pregnancy)
- avoid alcohol when trying
BMI and fertilisation
higher = harder
assisted contraception used when
fertility is a problem
IVF
age and fertilisation
natural Vs IVF
- Chances of successful pregnancy reduce as female gets older
- Success of IVF has similar trend
- IVF success is the same as natural pregnancy success
- Once fertilisation has occurred the implantation of the embryo has less chance of succeeding with age of mother (large drop after 34)
early pregancy stages
Timed from date of conception
- Ovulation and then fertilisation in fallopian tube
Zygote spends first week travelling down fallopian tube before implanting into uterus (day 8-9)
when embryo implanted into uterus
- undergoes developmental changes and maturity
- Significant change in size and complexity
stages of pregnancy
3 trimesters
- 0-12
- 13-28
- 29-40
characteristed by differnt stages in development
1st trimester development
0-12 weeks
structures of embryo are formed, tissues are differentiating
2nd trimester development
13-28 weeks
more specialisation and final differentiations
3rd trimester development
29-40 weeks
growth and acquisition of changes needed for successful birth
5 categories maternal changes in pregnancy
- Physical changes
- Hormonal changes
- Haematological changes
- Cardiovascular changes
- Coagulation Changes
physical changes in pregnancy
- total weight gain is 11-16kg
- Breasts 0.5kg; Placenta 0.7kg; Uterus 1.6kg; Baby 3.5kg; Amniotic Fluid 1-1.5kg; Extra blood volumes and fluids 4kg (important as blood loss during birth – protects mother from hypovolaemia if significant bleeding at birth)
- largest at 36 weeks before baby moves into birthing position lower down
3 hormonal changes in pregnancy
- increased oestrogen and progestogen
- lower oesphageal sphincter relaxes
- hormonal changes increase reduce insulin sensitivity
effect of increased osetrogen and progestogen in pregnancy
act on kidney to increase Renin secretion
- Increased salt & water retention
- Increased plasma volume by 45%
- Dilution effect makes Hb fall from 15-12g/dL - NORMAL
- Doesn’t keep place with increased plasma volume – will appear low Hb compared to volume, but the absolute amount of Hb carrying oxygen to tissues remains high
- Anaemia in pregnancy is often artificial anaemia as higher circulating volume but same Hb
- Protects against haemorrhage at birth
- Dilution effect makes Hb fall from 15-12g/dL - NORMAL
- Increased plasma volume by 45%
how does hormonal changes in pregnancy protect against haemorrhage at birth
increased oestrogen and progestogen = increase renin secretion = increase salt and water retention
- increased plasma volume by 45%
- Dilution effect makes - Hb fall from 15-12g/dL - NORMAL
- Doesn’t keep place with increased plasma volume – will appear low Hb compared to volume, but the absolute amount of Hb carrying oxygen to tissues remains high
Anaemia in pregnancy is often artificial anaemia as higher circulating volume but same Hb
effect of lower oesphageal sphincter relaxing in pregnancy
with increase abdominal pressure gievs increased risk of GORD
- issue - be aware
effect of reduced insulin sensitivity in pregnancy due to hormonal changes
diabetes in pregnancy - esp if somone prone to type II
- can result in change to mother and foetus
- larger, heavier baby =complications on delivery
4 haematological changes in pregancy
- increased production of RC, WC, Platelets
- 20% increase in RC mass
- Increased platelet consumption makes platelets normal to low
- Increased WC makes diagnosing infections difficult
2 cardiovascular changes in pregnancy
relaxation of vascular smooth muscle
vascular compresssion by uterus
effect of relaxation of vascular smooth muscle in pregnancy
- Reduced peripheral resistance
- Reduced systolic and diastolic blood pressure – help cope with inc circulatory load
- Compensatory increase in heart rate by 25%
effect of vascular compression by uterus in pregnancy
- Vena cava and aorta
- Difficulty with venous return when supine
- Pressure on baby on vessels when mother supine can cause significant compression
- Venous return through vena cava
- Aorta Arterial supply to body
- Allow mother to sit to one side or have a pillow under one area to help reduce this in dental care
- Pressure on baby on vessels when mother supine can cause significant compression
dental impact of vascular compression by uterus
Allow mother to sit to one side or have a pillow under one area to help reduce this in dental care
coagulation changes in pregnancy
- Coagulation screens remain normal
- Clotting factor production increases
- Fibrinolysis increases
- Increased system sensitivity with increased DVT risk
- can be complication
- but Increased sensitivity of coagulation system so any haemorrhagic issues in birth can be addressed rapidly
position of baby in abdomen effect
Increase compression of bladder and bowel as size of baby increases
- urgency
- bladder issues
6 food categories to not eat in pregnancy
- raw/slightly cooked meat and raw fish
- raw eggs
- non-pasteurised milk and milk cheese
- spicy, grilled and fried food
- marlin, tuna, shark
- liver and other entrails and internal organs of a slaughtered animal during the initial 3 months of pregnancy (e.g. haggis)
PASSING INFECTION FROM MOTHER TO BABY RISK
risk due to raw/slighly cooked meat and fish
danger of infection with toxoplasmosis
danger of raw eggs
salmonella
danger of non-pasteurised milk and milk cheese
listeria
danger of spicy, grilled and fried food
dyspepsia and GORD
danger of marlin, tuna and shark
mercury toxicity - on developing foetal brain
when does development start
week 4
- zygote becomes and embryo
- neural tube, gut tube and brain begin
week 6
start of embryonic circulation
- Weeks 6-10 embryonic development & growth
- Embryo stages stops at 10 weeks
weeks 10-14
foetus
- features and limbs become developed and active!
- Mother may feel
miscarriage rate highest
in first trimester (but can occur at any stage)
causes of miscarriage
- Maternal and foetal factors
- Most naturally – abnormal development in embryo or foetus (genetic change, ability to maintain nutrients)
second trimester development
(after week 14)
- Hair, nails toenails and eyelids start to form
- Movement may be felt
- 18 weeks – toes and fingers formed and hearing starts to respond (special sensoy start)
- 20-26 final development of vision and senses
- Brain development and body fat increase
18 weeks
toes and fingers formed and hearing starts to respond (special sensoy start)
20-26 weeks
- final development of vision and senses
- Brain development and body fat increase
third trimester development
- Growth and nervous system maturation (and lungs)
- Foetus will build up muscle and fat reserves in preparation of trauma of birth ahead
placenta
connects baby to mother
- interlinking mesh – maternal and foetal circulation do not mix
how does placenta work
sit in close proximity to each other so nutrients can diffuse easily from one to the other
- allows some infections and toxins to diffuse into foetus as well
- placental barrier can prevent some
- HIV cannot cross – acquired at birth
- placental barrier can prevent some
how to lower risk of infection spread (HIV esp)
HIV cannot cross placenta barrier
acquired through natural birth
- C-section less risky for child than normal delivery
placenta made of
Large vascular organ
capillary base joined through a stalk to child,
umbilical cord carries blood from foetal side to placenta (belly button)
labour stages
induction of labour
- first stage
- second stage
- third stage - placenta delivery
1st and 2nd delivery baby
stage of labour determined by
Depend on degree of dilation of cervix and how far baby is positioned through birth canal
forceps in labour
Aid delivery of baby
- Press sides of vagina away from baby’s - head making room for head to move lower down
- Should have no contact with baby head
ventoux in labour
- Suction cup applied to top of head
caesarean section
Through abdomen into uterus
- lower chance of spread of some infections e.g. HIV
umbilical cord healing
After birth umbilical cord is clamped
- Allows baby circulation to maintain its own oxygenation
- Vessels do not change – shut themselves off, allowing umbilical stump to necrose and fall off
reason for screening in pregnancy
looking to establish certain facts about pregnancy
e.g. dates, number, placental structures, ectopic pregnancy, anatomy
screening in pregnancy done by
ultrasound
6 reasons for screening in first trimester
- establish dates of a pregnancy
- to determine number of foetuses and identify placental structures
- diagnose an ectopic preganancy
- diagnose miscarriage
- examine the uterus and other pelvic anatomhy
- detect foetal abnormalities
why need to know number of foetuses
- multiple births in humans are not common
- complicated – tend to result in 2 smaller foetuses (less prepared for birth)
ectopic pregnancy
- development not taken place in uterus (implanted somewhere other than uterus)
- egg released in abdominal cavity or retain within fallopian tube
- can be a successful pregnancy but delivery will not be possible naturally
why need to screen placenta
- structure of placenta – failure of placenta development can compromise pregnancy
why look at pelvic anatomy of pregnacy screening
assess any possible delivery issues
18-20 week scan
10 points
detailed ultrasound
- to confirm pregnancy dates
- to determine the number of foetuses and examine the placental structures
- to assist in prenatal tests such as an amniocentesis
- to examine the foetal anatomy for presence of abnormalities
- to check the amount of amniotic fluid
- to examine blood flow patterns
- to observe foetal behavior and activity
- to examine the placenta
- to measure the length of the cervix
- to monitor foetal growth
amniocentesis
prenatal test
- amniotic fluid taken and has cells that have fallen of foetus
- genetic assessment of DNA of foetus can be made – examine chromosomes
screenings for mother for
chronic diseases e.g. diabetes
infectious diseases e.g. HIV, Hep B, Hep C
- can be passed at delivery to baby
- option for treatment during pregnancy possible but consideration to C section should be made – less chance of transmission
foetus scanned for
genetic and developmental abnormalities - choice
2 chronic diseases mothers screened for
hypertension - can cause preeclampsia - complicate pregnancy
diabetes
infections mother screened for (5)
- Rubella
- Syphilis
- hepatitis B
- Hepatitis C
- HIV
foetal testing in pregnancy referred to as
FAST – foetal abnormality screening programme
FAST
foetal abnormality screening programme
- Ultrasound and some blood tests to look for risk of chromosomal abnormalities
Combined results can suggest chromosome abnormality
at 1st and 2nd trimester and then birth
FAST tests done in 1st trimester
in 1st trimester 11-14 weeks
- Neuchal Translucency – Ultrasound transparency of tissue around the neck
- Maternal hCG - blood
- PAPP-P - blood
combined results can suggest chromosome abnormality
FAST tests done in second trimester
- AFP – alpha-fetoprotein
- Abnormality follow-up - follow up from early suspicion
- CVS & Amniocentisis – genetic changes
- Ultrasound – spina bifida
FAST tests done at birth
- Physical examination
- Hearing test
- Blood spot
blood spot done at birth for (5)
analysis for any metabolic disorders that will impair development
- Phenylketonuria - PKU
- Hypothyroidism
- Cystic Fibrosis
- Sickle cell disease
- MCADD – acyl CoA dehydrogenase deficiency
All manageable if aware the child has these problems – hence early identification key
APGAR Score stands for
Activity
Muscle tone
Pulse
>100/min
Grimace
Reflex irritability
Appearance
Colour
Respiration
rate
APGAR done at
1min and 5min
- should be significant rise in score between
- good APGAR score at 5 min = good prognosis
- depressed APGAR -> transfer to special care baby unit
Activity
Muscle tone
Pulse
>100/min
Grimace
Reflex irritability
Appearance
Colour
Respiration
rate
5 dental considerations in pregnancy
- Cost of dental care
- Free during pregnancy
- Drugs in pregnancy
- Not just affect the mother but affect foetus too – some may need avoided
- Pregnancy gingivitis
- Change in hormone levels making the vascularity response to plaque higher
- Periodontal health in pregnancy
- Position of mother
pregnancy gingivitis
Change in hormone levels making the vascularity response to plaque higher
