Hypertension in pregnancy

2. Management of
Hypertension in Pregnancy
Presented by-
Dr. Md. Abdul Maleque
MD (Cardiology), BSMMU
FCPS (Medicine – Final Part)
Clinical & Interventional Cardiologist
NICVD, Dhaka

3. Hypertension in pregnancy
• Hypertension, most common medical complication affecting
10-15% of pregnancies worldwide.
• The incidence is increasing day by day globally.
• Increased maternal and perinatal morbidity & mortality.
• Hypertensive disorders in pregnancy (BP ≥ 140 mmHg and /
≥ 90 mmHg) are the 2nd leading cause of maternal mortality
in Bangladesh (about 24%).
• One of the leading cause of maternal deaths (14%) globally.
• Maternal mortality is more likely to occur when BP ≥
160/110 mmHg.

4. Cardiovascular Physiology during
pregnancy
The hormonal changes of pregnancy induce significant adaptation in the
cardiovascular physiology of the mother.
(1) In 1st trimester; surges of estrogen, progesterone & relaxin
mediates NO release → systemic vasodilation.
(2) Renin-Angiotensin-Aldosterone system (RAAS) is augmented →
salt & water retention → plasma volume expansion→ physiologic
anemia (due to more plasma than RBC mass).
(3) This ↑ ventricular wall mass → ↑SV
(4) To compensate vasodilation & anemia, HR ↑
(5) ↑ SV & ↑ HR → ↑ CO

5. Physiological changes during pregnancy
• The cardiac output increases 40–50%
• Resting heart rate increases 30–35% ( 20/25 beats/min)
• stroke volume increases 13 - 15%
• SVR decrease in (-21%)
• The maternal BP (BP = CO × SVR) decrease 5-10 mmHg
• All returns to pre pregnancy level about 6 weeks after delivery
Cause:
(1) Smooth muscle relaxing effect of progesterone, NO, PG or ANP.
(2) Angiotensin –II is destroyed by angiotensinage
(3) The vascular system becomes refractory to angiotensin-II
(4) Increased vascular endothelial growth factor

8. Trophoblast Invasion and Uterine
Vascular Changes:

9. Hypertension in pregnancy
• Hypertension in pregnancy is defined simply as having a
systolic BP140 mmHg or more &/or diastolic BP 90 mmHg
or more ( office or in hospital ) (Davidson- On 2 separate
occasion at least 4 hrs apart).
• Risk factors: Describe later ( risk factors of pre-eclampsia)
• Grading:
• Mild: 140-159/90-109mmHg
• Severe: SBP ≥160 mmHg or DBP ≥110 mmHg
• Emergent : SBP ≥170 mmHg or DBP ≥110 mmHg

10. Classification
According to European Society of Cardiology (ESC)-2018
• Pre-existing hypertension/ Chronic hypertension ( 1st half of
pregnancy)
. Essential/primary hypertension
. Secondary hypertension
• Gestational hypertension ( 2nd half of pregnancy)
• Pre-eclampsia / Eclampsia
• Pre-existing hypertension superimposed with gestational
hypertension with proteinuria
• Antenatally unclassifiable hypertension

11. Classification
According to American College of Obstetricians & Gynecologists (ACOG)
-2019
• Chronic hypertension
• Gestational hypertension
• Preeclampsia - eclampsia
• Chronic hypertension with superimposed preeclampsia

12. Hypertension In pregnancy
Before 20 weeks
Of pregnancy
Chronic hypertension
In pregnant women
1.GestationalHypertension:
Blood pressure above
140/90 mmHg
After 20 weeks
Of pregnancy
2. Preeclampsia:
Blood pressure
>140/90 mmHg,
proteinuria
3. Eclampsia:
Preeclampsla
With convulsion

13. Pre-existing Hypertension/ Chronic
Hypertension
• Presence of hypertension of any cause that precedes
pregnancy or before the 20th weeks of gestational age and
persists more than 42 days / (12 weeks) post-partum.
• The high risk factors for developing complication:
(i) Age (> 40 years)
(ii) Duration of hypertension (>15 years)
(iii) Level of BP (>160/110 mm of Hg)
(iv) Presence of any medical disorder or thrombophilias
• Majority of CH have satisfactory maternal and fetal outcome

14. Pre-existing Hypertension/ Chronic
Hypertension
• Effect on pregnancy:
a) Maternal:
- Superimposed pre-eclampsia/eclampsia (20% cases)
b) Foetal:
- IUGR
- IUD

15. Gestational Hypertension
• A sustained rise of BP ≥ 140/90 mm Hg on at least two
occasions, ≥ 15 mins (4 or more hours) apart beyond the 20th
week of pregnancy and resolves within 42 days/ (Dav-12
weeks) post-partum.
• It should fulfill the following criteria:
(1) Absence of any underlying cause of HTN
(2) Unassociated PE (edema or proteinuria).
(3) Majority of cases are more than or equal to 37 weeks
pregnancy.
(4) Generally not associated with biochemical abnormalities
(5) The BP should come down to normal within 6 weeks
following delivery.

16. Comparison between Chronic &
Gestational HTN
Chronic
• Onset before 20 wks of
gestation
• ≥140/90 mm Hg
• H/O use of anti-
hypertensive before
pregnancy
• Persistence of HTN > 6wks
post-partum
• May superimposed with pre-
eclampsia
Gestational
• New-onset HTN after 20
wks of gestation
• ≥140/90 mm Hg
• No H/O of using
antihypertensive
• Transient diagnosis with
normal level by 6 wks post-
partum
• may evolve to pre-eclampsia

17. Pre-eclampsia
• Hypertension occurring after 20 wks of gestation with proteinuria,
maternal organ dysfunction or uteroplacental dysfunction (Dav).
• Gestational hypertension + significant proteinuria
Triad:
o Gestational HTN
o Proteinuria.
o Oedema
• HTN: BP ≥140/90 mm Hg ; a diastolic rise of blood pressure is
more important than the systolic rise .
• Proteinuria:. > 0.3 g/24h or 0.1 g/L
dipstick test ≥ 1+
ACR ≥ 30mg/mmol
• Blood pressure is more significant than proteinuria to predict fetal
& maternal outcome.
• The underlying basic pathology is endothelial dysfunction and intense
vasospasm

18. Preeclampsia(cont.)
High risk of preeclampsia:
• Hypertensive disease during
previous pregnancy
• Pre-existing medical
conditions:
. Chronic kidney disease
. Autoimmune disease eg:
SLE/antiphospholipid
Syndrome (APS)
. Type 1 & type 2 diabetes
. Chronic hypertension
Moderate risk of preeclampsia:
• First pregnancy
• Age 40 years or older
• Pregnancy interval more than 10
years
• Obesity (BMI ≥35 kg/m2 at first
visit)
• Family history of pre-eclampsia
• Multiple pregnancy

19. Clinical Types
• Mild /Non-severe:
BP ≥140/90 mm Hg but less than 160 /110 mm Hg
with mild proteinuria without signs-symptoms of organ
dysfunction, biochemical or hematological abnormalities.
• Severe:
(1) A persistent systolic blood pressure ≥ 160/110 mm Hg.
(2) Proteinuria – present (usually 3+ or more on dipstick test)
(3) Oliguria (< 400 mL/24 h)
(4) Platelet count less than 100,000/mm3.
(5) Elevated liver enzymes
(6) Cerebral or visual disturbances.
(7) Persistent severe epigastric pain.
(8) Retinal hemorrhages, exudates or papilledema.
(9) Intrauterine growth restriction of the fetus.
(10) Pulmonary edema.
(11)Serum creatinine > 1.1mg/dl

20. Symptoms
Pre-eclampsia is principally a syndrome of signs and when
symptoms appear, it is usually late.
Mild symptoms:
• swelling over the ankles on rising from the bed in morning
• tightness of the ring on the finger
• Gradually, the swelling may extend to the face, abdominal
wall, vulva and even the whole body

21. Symptoms
Alarming symptoms / ominous symptoms:
(1) Headache — either occipital or frontal
(2) Disturbed sleep
(3) Diminished urinary output—<400 mL / 24 hours
(4) Epigastric pain—acute pain in the epigastric region
associated with vomiting, at times coffee color ,due to
hemorrhagic gastritis or subcapsular hemorrhage in the
liver
(5) Eye symptoms—blurring, scotomata, dimness of
vision or at times complete blindness

22. Signs
1. Abnormal weight gain: > 4 lb a week is significant.
2. Rise of blood pressure: ≥140/90 mm Hg
3. Edema : generalized edema indicates imminent eclampsia.
4. no manifestation of chronic cardiovascular or renal pathology.
5. Pulmonary edema
6. On abdominal examination :evidences of chronic placental
insufficiency eg: scanty liquor or IUGR
Order of manifestations in preeclampsia:
rapid gain in weight → visible edema and/or hypertension →
proteinuria.

23. HELLP Syndrome:
• This is an acronym for-
• Hemolysis (H)
• Elevated Liver enzymes (EL) – >2 x normal
• Low Platelet count(LP) (<100,000/mm3).
• This is a complication of preeclampsia (10–15%) & may
develop even without maternal HTN
• Manifestations: nausea, vomiting, epigastric or right upper
quadrant pain with biochemical and hematological changes
• Hypertensive crisis: when the BP is >160/110 mmHg or the
mean arterial pressure (MAP) is >125 mm Hg

24. Complication of Pre-eclamsia
• Maternal:
a) During pregnancy: b) During labour:
- Eclampsia - Eclampsia
- Accidental haemorrhage - PPH
- AKI C) Puerperium:
- Dimness of vision even blindness - Eclamsia
- Pre term labour - Shock
- HELLP syndrome - Sepsis
- Cerebral haemorrhage
- ARDS

25. Complication of Pre-eclampsia
• Fetal:
- IUGR
- IUD
- Prematurity
- Asphyxia
● Remote:
- Persistent HTN
- Recurrent pre-eclampsia
- CVD
- CKD
- Risk of placental abruption

26. Eclampsia
• Eclampsia: Generalised seizures in a pregnant woman
previously diagnosed with pre-eclampsia ( occur in 1% pt).
Seizure rarely can occur before onset of HTN or proteinuria.
Triad:
oGestational HTN
oProteinuria.
oTonic-clonic seizures &/or coma appear in a pregnant
Woman.
• Cause of convulsion:
(1) Anoxia — spasm of the cerebral vessels → increased cerebral
vascular resistance → fall in cerebral oxygen consumption → anoxia,
(2) Cerebral edema
(3) Cerebral dysrhythmia
(4)Excessive release of glutamate
(5)loss of cerebrovascular autoregulation

27. Chronic Hypertension with superimposed
pre-eclampsia
• Criteria for diagnosis of superimposed pre-eclampsia:
. Aggravation of HTN
. New onset of proteinuria > 0.5 g/24 hrs specimen
. Development of HELLP syndrome
. Development of headache, blurring of vision, epigastric pain

28. Antenatally unclassifiable hypertension
• Antenatally unclassifiable hypertension:
this term is used when BP is first recorded after 20 weeks of
gestation and it is unclear if hypertension was pre-existing.
Reassessment 6 weeks post-partum will help distinguish pre-
existing from gestational hypertension.

29. Management of Hypertension in Pregnancy
• Objectives are:
(1) To stabilize hypertension
(2) To prevent the complications
(3) To prevent eclampsia
(4) Delivery of a healthy baby in optimal time
(5) Restoration of the health of the mother in puerperium.
• Management depends on :
• Maternal BP
• gestational age
• presence of maternal and fetal risk factor

30. Management
• Optimal management :
. Maintaining the BP around 110-140/80-90 mmHg by using
appropriate antihypertensive
. Regular assessment for the development of pre-eclampsia
. Close surveillance of fetal growth and wellbeing
* Home blood pressure monitoring may form part of this
assessment.

31. Treatment Goals
• ISSHP: The International Society for the Study of Hypertension in
Pregnancy
. Treatment is initiated for BP≥ 140/90, while urgent treatment &
hospitalization are indicated for BP ≥ 160/110 mmHg
. Antihypertensive are indicated to maintain BP : 110-140/80-85
mmHg
. Try to avoid hypotension- causes placental hypoperfusion & leads
to increase risk of IUGR, stillbirth & miscarriage.
● ACOG: recommends initiating treatment for BP ≥ 160/110 mmHg in the
absence of evidence of organ damage.

32. Management
• Antihypertensive drugs to avoid in pregnancy
▪ ACE inhibitors & ARBs - Contraindicated
▪ Diuretics – Avoid
▪ Beta blockers ( other than Labetalol) - Avoid
▪ Calcium Channel blockers ( other than Nifedipine, Amlodipine &
Diltiazem) - Avoid
• Antihypertensive drugs that can be safely used in pregnancy
▪ Labetalol: 100 mg bd – 400 mg tds
▪ Nifedipine controlled release: 30 mg daily – 60 mg bd &
Amlodipine
▪ Methyldopa : 250 mg bd – 750 mg tds
▪ Hydralazine : 25 mg tds – 50 mg tds
▪ Prazosin : 0.5 mg bd – 5 mg tds & Doxazosin : not available

33. Investigations
Essential:
• Full blood count with platelet count
• Urinalysis
• Serum creatinine
• Serum uric acid: biochemical marker of preeclampsia (>4.5mg/dl)
• Liver function test
• Test for proteinuria : in early & second half of pregnancy
- A positive urine dipstick shoud be followed with 24 hr urine protein
or albumin creatinine ratio : <30 mg/mmol-normal
● RBS – to see co-morbidities
● ECG – long standing hypertension
● Antenatal fetal monitoring
Optimal :
• Doppler USG of uterine arteries
• USG of kidney
• USG of adrenal gland & plasma & urinary fractionated metanephrine assays to exclude
pheochromocytoma
• Ophthalmoscopic examination
• A soluble fms-like tyrosine kinase 1:placental growth factor ratio : 38 or less exclude pre-eclampsia

34. General management
• Rest
• Diet: adequate amount of protein (about 100 g) ,Usual
amount of Fluids & salt, Total calorie appr.1,600 cal/day.
• Close monitoring
oSerial assessment of maternal symptoms and fetal
movement (daily by the woman)
oSerial Measurement of BP
oAssessment of platelets counts and liver enzymes
(weekly)

35. Pharmacological Management
• Drug treatment-options are limited:
➢Antihypertensive
o Labetalol & Methyldopa – most commonly used
oNifedipine
oHydralazine
oACE inhibitor, ARB, direct renin inhibitors are strictly
contraindicated
➢Corticosteroids for lung maturity
➢Magnesium sulfate for prevention of convulsion .
➢Diuretics:
1) Cardiac failure
(2) Pulmonary edema
(3) Massive edema

36. Pharmacological Management
• Initiation of antihypertensive: at >140/90mmHg
✓gestational HTN or
✓preexisting HTN superimposed with gestational HTN
✓HTN with subclinical organ damage or symptom
• All other women should start at ≥150/95mmHg
• Target:
. No evidence currently supporting target BP.
. A BP target of < 140/90 mmHg is suggested for pregnant
women receiving antihypertensive therapy.

37. Treatment of Chronic Hypertension
• Advice for pregnant women with chronic hypertension:
. Weight management
. Exercise
. Healthy eating
. Low salt intake
● Antihypertensive treatment :
. Sustained SBP ≥ 140 mmHg &/or DBP ≥ 90 mmHg
●Target : target BP 135/85 mmHg
● BP monitoring: Once or twice in a week until target achieved

38. Treatment of Chronic Hypertension
• Antihypertensive drugs :
. Consider Labetalol as 1st line drug
. Consider Nifedipine , if labetalol is not suitable
. Consider Methyldopa, if labetalol & nifedipine are not suitable
● Ecosprin:
. 75 – 100 mg once daily from 12 weeks
● Placental growth factor ( PlGF):
. Based testing to help rule out preeclampsia between 20 weeks &
upto 35 weeks of pregnancy, if women with chronic hypertension are
suspected of developing pre-eclampsia.
● Bed rest: do not offer bed rest as a treatment of gestational
hypertension

39. Common Oral Antihypertensive Agents in Pregnancy
Drug Dose Comments
Labetalol 200-2400 mg/d orally in 2-3 dlvided
dose
Avoid in patients with asthma and
CCF
Nifedipine 30-120 Mg/d orally of a slow release
preparation
Avoid sublingual form
Methyldopa 0.5-3g/d orally in 2-3 divided doses May not be effective in control of
severe hypertension

40. Agents for urgent BP control in Pregnancy
(for Severe hypertension)
Drug
Labetalol
Hydralazine
Nifedipine
Dose
10-20 mg lV bolus over 2
mins, then10-20 mg every
10 mins if BP remains >
160/110 mmHg to a max of
300mg
5 mg IV bolus, then 5-10
mg every 20-40 mins if BP
remains > 160/110 mmHg
10-20 mg orally, repeat in
30 mins if needed, then 10-
20 mg every 2-6 hrs
Comments
First line agent
fewer adverse
effects(bradycardia,
bronchospasm)
Contraindicated in Asthma,
CCF
Higher of frequent doses
associated with maternal
hypotension, fetal distress
Reflex tachycardia,
headache, flushing

41. • Hydralazine is no longer the drug of choice but still in use
when other treatment regimen fails
• IV urapidil can also be used
• Sodium nitroprusside should only be used as the drug of last
choice as prolonged treatment causes foetal cyanide
poisoning
• Drug of choice of PE with pulmonary edema is nitroglycerin

42. Labetalol dosing
• Oral: 100 mg PO q12 initially, increase 100 mg q12 hourly
every 2-3 days. 200-400 mg PO q12 hours.
• Maximum dose: 2400 mg / day.
• Hypertensive emergency:
Loading infusion – 20 mg IV over 2 min initially then 40-80
mg IV q 10 min , total dose not to exceed 300 mg.
or
1-2mg/min by continuous infusion ( total 300mg)
Continuous infusion- 2-6mg/hour.

43. Anticonvulsants
• Consider Magnesium sulfate
• If one or more features of severe pre-eclampsia present:
. Ongoing or recurring severe headache
. Visual disturbance
. Excessive nausea or vomiting
. Epigastric pain
. Oliguria and severe hypertension
. Progressive deterioration in laboratory blood tests ( rising
creatinine or liver transaminase, falling platelet count)
● Do not use diazepam, phenytoin or other anticonvulsants as an
alternative to magnesium sulfate.

44. Magnesium Sulfate
• Effective anticonvulsant
• No CNS depression
Indications:
• Severe Preeclampsia
• Eclampsia
• HELLP Syndrome
Contraindication:
• Myasthenia gravis
• Renal failure
Dosage Schedule
Intramuscular: Pritchard regime
. Loading Dose—4 g (20% solution) IV
over 3–5 minute followed by 10 g (50%),
deep IM(5 gm in each buttock)
. Maintenance Dose- 5 g (50%) IM 4
hourly in alternate buttock
Intravenous: Zuspan or Sibai regime
. Loading dose: 4–6 g IV slow over15–20
minute
. Maintenance :1–2 g/h IV infusion for
24 hours.
. If the woman has had an epileptic fit ,
the infusion should be continued for 24
hours after the last fit.

45. Magnesium Sulfate
• Magnesium Toxicity
Loss of deep tendon reflexes
Decreased respiratory rate (<12 per minute)
Urine output (< 30 mL/h)
Chest pain, heart block
• Management for Magnesium Toxicity
• Stop magnesium therapy
• Estimation of serum magnesium and creatinine levels
• Injection calcium gluconate 10 mL (10% solution), IV
slowly
• O2 , secure airway, ventilation if necessary

46. Obstetric Management
Curative treatment is delivery of the baby
Timing of delivery depends on —
(1) severity of the disease,
(2) duration of pregnancy
(3) response to treatment
(4) Maternal & Fetal condition
Immediate termination of pregnancy is indicated in –
• preeclampsia with visual disturbance or hemostatic
disorders
• eclampsia
• 37 completed wks in asymptomatic
Methods of delivery: either vaginal or Cesarean section
depending on obstetric factors

47. Prevention
Although there is no current method of preventing pre-eclampsia but
following measures are helpful.
• Preconception counselling
• Regular antenatal check up
• Antithrombotic agents: 100-150 mg aspirin is recommended daily from
12 wks to 36-37 wks of pregnancy who are at high risk.
• Heparin or LMWH: in women with thrombophilia
• Calcium supplementation : 1.5-2 g/day
• Balanced diet rich in protein
• Regular exercise
• Vitamin C & E do not decrease risk rather associated with low birth
weight < 2.5 kg & adverse perinatal outcome.

48. Prevention
• Observation/ antenatal check up for high risk mother:
. Maternal:
- BP twice daily
- Oedema daily
- Urine volume & proteinuria daily
- Body weight twice weekly
- Fundoscopy once weekly
- Platelet count, liver enzymes, renal function, uric acid on
admission & accordingly
. Fetal:
- Daily foetal movement
- Serial sonography

49. Prevention
• Mechanism of action of aspirin in pre-eclampsia:
# Improvement in the placentation process.
# Inhibition of platelet aggregation & its antithrombotic effect, thereby
leading to lower levels of placental infarct.
# Anti-inflammatory effects & endothelial stabilization.

51. Complications
• Maternal:
➢placental abruption
➢stroke
➢multiple organ failure
➢DIC
• Fetal:
➢IUGR
➢Prematurity
➢ IUD

52. HTN in Post-partum Period
• Methyldopa should be avoided-postpartum depression(30%)
• All antihypertensive agents are excreted into breast milk
• Risk of recurrence of HTN in subsequent pregnancy - very
high
• Long term cardiovascular consequence : increased risk of-
✓HTN
✓stroke
✓IHD
• Choice of drugs: Any drug
• Follow up : 2wks, 6-8 wks and then annual check up of BP
and metabolic factors are recommended .

53. Post partum pre-eclampsia/ Eclampsia
• About 5.7% of cases pre-eclampsia or eclampsia may present de novo
in the post partum period (upto 6 weeks) , even without
hypertension in pregnancy.
• These women often present with new onset persistent headache or
visual changes.
• A high clinical index of suspicion is crucial ( e.g- check BP, perform
urinalysis & consult with obstetrician).

54. Blood pressure monitoring after delivery
• Blood pressure normally peaks 3 to 6 days postpartum in both
normotensive women & those with previous hypertension due to:
. Pain
. Drugs ( e.g., NSAID)
. Excess fluid administration
. Restoration of vascular tone to pre-pregnancy level
• So, blood pressure should be measured at least once on 3rd to 6th
day after delivery.

55. Important Recommendation & Take Home
Message
• All pregnant women should be educated on signs and symptoms of hypertensive disorder
and importance of early diagnosis & prompt treatment.
• Antihypertensive:
A) During pregnancy:
. Initiation of antihypertensive according to BP level – be judicious
. SBP>170mmHg or DBP>110 mmHg: is an emergency & need
hospitalization , preferably treated with IV Labetalol
. PE with pulmonary edema: IV nitroglycerin
. ACE inhibitor, ARB, direct renin inhibitors are strictly contraindicated
B) Postpartum:
. If hypertension persist , any of recommended drugs except Methyldopa ( postpartum
depression)
C) Breastfeeding:
. All anti hypertensive excreted into breast milk at low concentrations. Avoid atenolol,
propranolol, nifedipine ( high conc. in milk). Prefer long acting CCBs. Diuretics suppress
lactation.

56. Important recommendation &Take
Home Massage
• Aspirin:
. Low dose aspirin (100-150mg daily) from 12 to 37 wks at high or moderate
risk patients.
• Delivery:
. GHTN or mild PE: Delivery at 37 wks
. PE with visual disturbance or hemostatic disorders: Expedite delivery/
Termination
• Long term consequences:
. Increase risk of HTN, CVD ( stroke, IHD), CKD in later life.
● Risk of recurrence of Hypertensive disorder:
. Increased risk of recurrence of HTN in subsequent pregnancy, earlier the onset
of HTN, the higher the risk of recurrence.