SALSO -

1. Hypertension in Pregnancy
Dr Lim Soon Hock MRCOG
Sarawak General Hospital

2. Introduction
 Hypertensive disorders of pregnancy (HDP) remains
as one of common causes of maternal mortality in
Malaysia.
 Accounted for 14.1% of total maternal death between
1997-2000 (Confidential Enquiry of Maternal Mortality,
Malaysia 2005)
 Carry risk for the woman such as eclampsia, DIVC,
intracranial bleeding, VTE, pulmonary oedema, heart
failure, abruptio placentae and death.
 Most develop for the first time in the second half of
the pregnancy.
 Carry risk for the baby: higher rate of perinatal
mortality, preterm birth and low birth weight.

3. Basic Stuff
 Chronic hypertension: Hypertension present at
booking visit or before 20 weeks, or that is being
treated at time of referral to maternity services.
Can be primary or secondary in aetiology.
 Gestational hypertension: New hypertension
presenting after 20 weeks without significant
proteinuria.

4. Basic Stuff
 Eclampsia: Convulsive condition associated with
pre-eclampsia.
 Pre-eclampsia: New hypertension presenting
after 20 weeks with significant proteinuria.
 Severe pre-eclampsia: Pre-eclampsia with
severe hypertension and/or with symptoms,
and/or biochemical and/or haematological
impairment.
 Significant proteinuria: urinary
protein:creatinine ratio >30mg/mmol or 24 hour
urine collection >300mg/day.

5. Severity of hypertension
Degree SBP DBP
Mild 140-149 90-99
Moderate 150-159 100-109
Severe ≥160 ≥110

6. Risk factors for pre-eclampsia
Moderate
 First pregnancy
 Age ≥ 40 years
 Pregnancy interval > 10 years
 BMI ≥ 35 kg/m2 at first visit
 Family history of pre-eclampsia
 Multiple pregnancy

7. Risk factors for pre-eclampsia
High
 Hypertensive disease during previous
pregnancy
 Chronic kidney disease
 Autoimmune disease such as systemic lupus
erythematosis or antiphospholipid syndrome
 Type 1 or type 2 diabetes
 Chronic hypertension

8. If at least 2 moderate risks factors or
one high risk factor for PET
Advise woman to take
aspirin 75 mg/day from 12
weeks until birth*
*NICE Hypertension in pregnancy August 2010

9. Evidence
 Cochrane systematic review of 59 RCTs involving
37 560 women was conducted to determine the
effectiveness of antiplatelet agents (mainly
aspirin) in reducing the risk of preeclampsia and
its complications.*
*Duley L, Henderson-Smart DJ, Meher S et al. Antiplatelet agents for
preventing pre-eclampsia and its complications. Cochrane Database of
Systematic Reviews 2007;(2)CD004659.

10. Evidence
 antiplatelet agents were associated with a
statistically significant reduction in the risk of pre-
eclampsia (RR 0.83; 95% CI 0.77 to 0.89).
 Antiplatelet agents were associated with a
statistically significant reduction in the risks of
preterm birth before 37 weeks (RR 0.92; 95% CI
0.88 to 0.97) and fetal and neonatal deaths (RR
0.86; 95% CI 0.76 to 0.98).

11.  A meta-analysis using individual-patient data
assessed the effectiveness of antiplatelet agents
(mainly aspirin) in risk reduction for pre-eclampsia
(N= 32217 women, 32819 babies) showed a
statistically significant reduction in risk of
developing pre-eclampsia (RR 0.90; 95% CI 0.84
to 0.97).*
*Askie LM, Duley L, Henderson-Smart DJ et al. Antiplatelet
agents for prevention of pre-eclampsia: a meta-analysis of
individual patient data. Lancet 2007; 369:(9575)1791-8.

12.  Points worth noting:
 NNT: 114 to prevent one case of PET.
 10% reduction in pre-eclampsia in high-risk
women receiving antiplatelet agents.
 10% reduction in preterm birth.
 No difference between those who started before
or after 20 weeks.

13. Is aspirin safe?
 There were no statistically significant differences
between women receiving antiplatelet agents and
those receiving placebo in the incidence of
potential adverse effects such as antepartum
haemorrhage, placental abruption or postpartum
haemorrhage*
*Askie LM, Duley L, Henderson-Smart DJ et al.
Antiplatelet agents for prevention of pre-
eclampsia: a meta-analysis of individual patient
data. Lancet 2007; 369:(9575)1791-8.

14. Outline of Management of Pre-
eclampsia (PET)
 Antihypertensives:
 Aim for BP<150/80-100mmHg.
 First-line: labetalol (oral, IV)
 Second-line: Nifedipine, methyldopa
 Monitor BP every 4 hours, hourly if
severe HPT.
 Check FBC, PT/PTT, BUSE, Se
Creatinine, Se Uric acid.

15. Outline of Management of Pre-
eclampsia (PET)
 Fetal Monitoring:
 USS for fetal growth + AFI + Umbilical artery
doppler every 2 weekly.
 CTG: at diagnosis and repeat if reduced
fetal movement, PV bleeding, abdo pain,
deterioration of maternal condition
 Steroids: IM dexamethasone 12mg BD for 2
doses if considering delivery within 7 days
(24 to 36 weeks) for fetal lung maturity.

16. Outline of Management of Pre-
eclampsia (PET)
 Timing of delivery:
 Determine by several factors:
 Severe refractory hypertension
 Deteriorating maternal or fetal conditions.
 Availability of neonatal care.
 Completion of corticosteroid.
 After 37+0 weeks: recommend birth within
24-48 hours.

17. Magnesium sulphate
 Magpie trial (Lancet 2002,N= 10,141)
 Significantly fewer eclamptic fits (0.8%
Vs 1.9% with placebo) - 58% lower
relative risk of eclampsia.
 A significant reduction in maternal
mortality (0.2% Vs 0.4% with placebo)
- 45% reduction in relative risk.
 Significantly lower risk of placental
abruption (2% Vs 3.2% with placebo)

18. Indications for MgSO4
 Give intravenous magnesium sulphate if
woman with severe hypertension or
severe pre-eclampsia has or previously
had eclamptic fit.
 Consider giving intravenous
magnesium sulphate* if birth planned
within 24 hours in woman with severe
pre-eclampsia.

19. Features of severe pre-eclampsia
 Severe hypertension and proteinuria or mild or
moderate hypertension and proteinuria with at
least one of:
 severe headache
 problems with vision such as blurring or flashing
 severe pain just below ribs or vomiting
 Papilloedema
 signs of clonus (≥ 3 beats)
 liver tenderness
 HELLP syndrome
 platelet count falls to < 100 x 10 9 /litre
 abnormal liver enzymes (ALT or AST rises to > 70
iu/litre).

20. Cochrane systematic review
(6 RCT, n = 11,444)
 magnesium sulphate was statistically
significantly better than none/placebo in
preventing eclampsia (RR 0.37- 0.44)
 No statistically significant differences in :
maternal death, serious maternal
morbidity, pulmonary oedema, placental
abruption, kidney dialysis, stillbirth and
neonatal death rates.
* Duley L, Gulmezoglu AM, and Henderson-Smart DJ. Magnesium sulphate and
other anticonvulsants for women with preeclampsia. Cochrane Database of
Systematic Reviews 2008;(3).

21. MgSO4 regime*
 Loading dose of 4 g given intravenously
over 5 minutes, followed by infusion of 1
g/hour for 24 hours.
 Further dose of 2–4 g given over 5
minutes if recurrent seizures.
*The Eclampsia Trial Collaborative Group (1995)
Which anticonvulsant for women with eclampsia?
Evidence from the Collaborative Eclampsia Trial.
Lancet 345:1455–63.

22. Outline of Management of Pre-
eclampsia (PET)
 Fluid balance: limit fluid to 2L/day (total)
 Mode of delivery: according to clinical
circumstances and woman’s preference.

23. Postnatal care
 Breastfeeding:
 No known adverse effects: labetalol,
nifedipine, enalapril, captopril, atenolol,
metoprolol.
 Insufficient evidence on safety: ARBs,
amlodipine, ACE inhibitors other than
enalapril & captopril.

24. Next pregnancy?
 Risk of PET: ranges from 1 in 14 to 1 in
2.
 If birth before 34 weeks: 1 in 4.
 If birth before 28 weeks: 1 in 2.