Pre-eclampsia Flashcards
where is preeclampsia more common?
africa and asia
how is pre-eclampsia diagnosed?
- New onset hypertension (previously normotensive woman) BP ≥140 mmHg systolic and/or ≥90 mmHg diastolic
- Occurring after 20 weeks’ gestation
- Reduced fetal movement and/or amniotic fluid volume (by ultrasound) in 30% cases
- Oedema common but not discriminatory
- Headache
- Abdominal pain
- Visual disturbances, seizures and breathlessness associated with severe PE and risk of eclampsia (seizures)
what are the subtypes of pre-eclampsia?
early onset (<34 weeks)
late onset (>34 weeks)
what are the differences in the effect on the mother and fetus between early and late onset pre-eclampsia?
early onset- assocaited with fetal and maternal symptoms and changes in placental structure
late onset- more common, mostly maternal symptoms and fetus okay, less over/no placental changes
what are the risk factors for pre-eclampsia?
- Previous pregnancy with pre-eclampsia
- BMI >30 (esp >35)
- Family history
- Increased maternal age (>40, <20?)
- Gestational hypertension or previous hypertension
- Pre-existing conditions: diabetes, PCOS, renal disease, subfertility, autoimmune disease.
- Non-natural cycle IVF?
what are the risks to the mother from pre-eclampsia?
- Damage kidneys, liver, brain and other organ systems
- Possible progression to eclampsia (seizures, loss consciousness)
- placental abruption (separation of the placenta from the endometrium)
what are the risks to fetus from pre-eclampsia?
- reduced fetal growth
- preterm birth
- pregnancy loss/ stillbirth
what are the placental defects underepinning pre-eclampsia?
normal
- EVT invasion of maternal spiral arteries leads to endothelial and smooth muscle breakdown
- EVT becomes endothelial EVT and spiral arteries become high capacity
pre-eclampsia
- EVT invasion of maternal spiral arteries is limited to decidual layer
- spiral arteries not extensively remodeled
- placental perfusion is restricted
what is the role of Flt1 and PIGF in maternal symptoms?
PLGF (placental growth factor):
- VEGF related
- pro-angiogenic factor released in large amounts by the placenta
Flt1: soluble VEGFR1
- soluble receptors of VEGF-like factors
- binds soluble angiogenic factors to limit their bioavailability
role in PE:
- excess production Flt1 by distressed placental -> reduction of available pro-angiogenic factors in maternal circulation -> endothelial dysfunction
how is pre-eclampsia detected?
PLGR levels alone or Flt-1/PIGR ration can be use ot predict onset of PE
what are the results expected in PLGR alone pre-eclampsia secreening?
triage test that rules out PE in next 14 days in women 20-37 weeks
<12 highly abnormal
12-100 abnormal
>100 normal
highly abnormal or abnormal -> increased risk for preterm delviery within 14 days of test
what are the normal levels for sFlt-1/PIGF ratio?
<38- rule out pre-eclampsia
>38 - increased risk of pre-eclampsia
gestation period = 24-36 weeks plus 6 days
what is the management of pre-eclampsia?
- can only be resolved by delivery of placenta
- if <34 weeks: preferable to try and maintain pregnancy if possible for benefit of fetus
- if >37 weeks: delivery preferable
- in between: case by case basis
antihypertensive therapies and corticosteroids for <34 weeks to promote fetal lung development pre delivery
how is pre-eclampsia prevented?
3 main approaches:
- weight loss (esp if BMI>35)
- exercise throughout pregnancy (seems to work independent of BMI)
- low dose aspirin (from 11-14 weeks) for high-risk groups
- but may only prevent early onset
