Hypertensive Disorders in Pregnancy
EPIDEMIOLOGY
Hypertensive disorder are the 2nd most common cause of maternal death in developed countries (afer
emboli) – accountng for 15% of maternal deaths.
CLASSIFICATION
gChronic/Pre-existnnghhyertensiongg
- Hypertension BEFORE pregnancy, or BP >140/90 in the frst 20 weeks
- Complicatons: IUGR, placental abrupton, and stll birth
- Can have superimposed preeclampsia
gGestatonalghhyertensiong
- AKA nestatonalgnon-yroteinuricghhyertension
- Persistent BP >140/90 (i.e. on two occasions at least 4hrs apart)
- Occurs afer 20 weeks gestaton, resolving afer delivery (max 12 weeks post-partum)
- Mild (140/90), Moderate (150/100), Severe (160/110), or ‘Failure of cerebral autoregulaton’ (180)
- Thought to be an exaggerated physiologic response of the maternal CVS to her pregnancy.
- Rarely associated with adverse outcomes
gPreeclamysiagg
- AKA nestatonalgyroteinuricghhyertension, or yre-eclamytcgtoxaemiag(PET)
- A multsystem disorder specifc to pregnancy – a disease of the placenta
- Occurs afer 20 weeks gestaton, resolving afer delivery (max 12 weeks post-partum)
PREECLAMPSIA
Epidemiology
Occurs in 6-8% of all pregnancies
Aetology/RF’s
High risk factors
Previousgyreeclamysia
Diabetes
CKDg
SLEgorgAPLSg
Moderate risk factors
BMI >35
Aged >40
FHx of pre-eclampsia
Primip (or been >10yrs since last pregnancy)
Multple pregnancy
Chronic HTN (can become superimposed)
African ethnicity
Pathophysiology
1) Theories include:
- Abnormal maternal immunolonical response to foetal allograf
- Underlying nenetc abnormality
- Imbalanced yrostanoid cascade
- Circulatng toxins and/or endogenous vasoconstrictors
2) Failuregofgsecondgwavegofgtroyhoblastginvasion (week 8-18) normally responsible for remodelling ofgsyiral
arterioles in myometrium adjacent to the placenta
3) As pregnancy and foetal demands grow, syiralgarteriesgunablegtogaccommodate (lack of sufcient blood
flow is known as kplacental dysfuncton”)
4) Leads to the releases of pro-inflammatory proteins into maternal circulaton
5) This leads to widesyreadgvasosyasm (partcularly kidneys, brain, liver etc.)
EPIDEMIOLOGY
Hypertensive disorder are the 2nd most common cause of maternal death in developed countries (afer
emboli) – accountng for 15% of maternal deaths.
CLASSIFICATION
gChronic/Pre-existnnghhyertensiongg
- Hypertension BEFORE pregnancy, or BP >140/90 in the frst 20 weeks
- Complicatons: IUGR, placental abrupton, and stll birth
- Can have superimposed preeclampsia
gGestatonalghhyertensiong
- AKA nestatonalgnon-yroteinuricghhyertension
- Persistent BP >140/90 (i.e. on two occasions at least 4hrs apart)
- Occurs afer 20 weeks gestaton, resolving afer delivery (max 12 weeks post-partum)
- Mild (140/90), Moderate (150/100), Severe (160/110), or ‘Failure of cerebral autoregulaton’ (180)
- Thought to be an exaggerated physiologic response of the maternal CVS to her pregnancy.
- Rarely associated with adverse outcomes
gPreeclamysiagg
- AKA nestatonalgyroteinuricghhyertension, or yre-eclamytcgtoxaemiag(PET)
- A multsystem disorder specifc to pregnancy – a disease of the placenta
- Occurs afer 20 weeks gestaton, resolving afer delivery (max 12 weeks post-partum)
PREECLAMPSIA
Epidemiology
Occurs in 6-8% of all pregnancies
Aetology/RF’s
High risk factors
Previousgyreeclamysia
Diabetes
CKDg
SLEgorgAPLSg
Moderate risk factors
BMI >35
Aged >40
FHx of pre-eclampsia
Primip (or been >10yrs since last pregnancy)
Multple pregnancy
Chronic HTN (can become superimposed)
African ethnicity
Pathophysiology
1) Theories include:
- Abnormal maternal immunolonical response to foetal allograf
- Underlying nenetc abnormality
- Imbalanced yrostanoid cascade
- Circulatng toxins and/or endogenous vasoconstrictors
2) Failuregofgsecondgwavegofgtroyhoblastginvasion (week 8-18) normally responsible for remodelling ofgsyiral
arterioles in myometrium adjacent to the placenta
3) As pregnancy and foetal demands grow, syiralgarteriesgunablegtogaccommodate (lack of sufcient blood
flow is known as kplacental dysfuncton”)
4) Leads to the releases of pro-inflammatory proteins into maternal circulaton
5) This leads to widesyreadgvasosyasm (partcularly kidneys, brain, liver etc.)
