Disorders of Pregnancy and Parturition

Question 1

What are the 7 diagnostic features of pre-eclampsia?

Answer 1

1. New onset hypertension (in a previously normotensive woman) BP ≥140 mmHg systolic and/or ≥90 mmHg diastolic
2. Occurring after 20 weeks’ gestation
3. Reduced fetal movement and/or amniotic fluid volume (by ultrasound) in 30% cases
4. Oedema common but not discriminatory for PE
5. Headache (in around 40% of severe PE patients)
6. Abdominal pain (in around 15% of severe PE patients)
7. Visual disturbances, seizures and breathlessness associated with severe PE and risk of eclampsia (seizures)

Question 2

What are the sub-types of pre-eclampsia?

Answer 2

Early onset: <34 weeks
Associated with fetal and maternal symptoms
Changes in placental structure

Late onset: >34 weeks
More common (90%)
Mostly maternal symptoms
Fetus generally OK
Less overt/no placental changes

Question 3

What are maternal risk factors?

Answer 3

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?

Question 4

What are risks to the fetus and mother?

Answer 4

Mother:
Damage to kidneys, liver, brain and other organ systems
Possible progression to eclampsia (seizures, loss of consciousness)
Placental abruption (separation of the placenta from the endometrium)

Fetus: reduced fetal growth, preterm birth, pregnancy loss/stillbirth

Question 5

What placental defects underpin pre-eclampsia?

Answer 5

PE (esp early): EVT invasion of maternal spiral arteries is limited to decidual layer. Spiral arteries are not extensively remodelled, thus placental perfusion is restricted.

Question 6

What is PLGF and Flt-1?

Answer 6

PLGF: Placental Growth Factor
VEGF related, pro-angiogenic factor released in large amounts by the placenta.
Flt1 (soluble VEGFR1)
Soluble receptor for VEGF-like factors which binds soluble angiogenic factors to limit their bioavailabliltiy.

Question 7

What is the relationship between PLGF and Flt-1 with pre-eclampsia?

Answer 7

Excess production of Flt-1 by distressed placenta leads to reduction of available pro-angiogenic factors in maternal circulation, resulting in endothelial dysfuction.