Hypertension in Pregnancy

2. HYPERTENSION IN PREGNANCY
DR AHMAD AMIN
PGR CARDIOLOGY
MTI-MMC, MARDAN

3. DEFINITIONS (AHA)
• Hypertension in pregnancy: systolic BP equal to or greater than 140 mm Hg, or
diastolic BP equal to or greater than 90, or both measured on two occasions at least 4
hours apart.
• Severe-range hypertension: systolic BP equal to or greater than 160 mm Hg, or
Diastolic BP equal to or greater than 110 mm Hg, or both measured on two occasions
at least 4 hours apart.(unless anti-hypertensive therapy initiated before this time).
• Chronic hypertension: Diagnosed or present before pregnancy, OR before 20 weeks of
gestation, OR Hypertension that is diagnosed for the first time during pregnancy and
that does not resolve in the post partum period.
• Gestational hypertension: Hypertension diagnosed after 20 weeks of gestation in a
previously normal BP.
• Chronic hypertension with superimposed pre-eclampsia: Pre-eclampsia in a woman
with a history of hypertension before pregnancy, or before 20 weeks of gestation.

5. • Pre-eclampsia with severe features: severe range HTN and
proteinuria (with or without signs & symptoms of significant end-organ
dysfunction), Or systolic BP >=140 or diastolic BP >= 90 with or without
proteinuria and one or more of the following sign and symptoms of significant
end organ dysfunction;
New onset cerebral of visual disturbances
Severe persistent RUQ or epigastric pain unresponsive
to medication OR ALT or AST >= 2 times ULN or both
Thrombocytopenia < 100K
Renal insufficiency
Pulmonary edema

6. RISK FACTORS
Past hx of pre-eclampsia
Pre-existing HTN
Pre-gestational Diabetes
Multi-fetal gestations
CKD
Autoimmune diseases (e.g. APLS, SLE)

7. Pre-pregnancy BMI > 25 or BMI in pregnancy >20
Nulliparity
Family hx of pre-eclampsia
Prior pregnancy complications associated with placental
insufficiency (IUGR, Abruption, Or Still birth)
Advanced Maternal age
Use of assisted reproductive technologies
Women who smoke have low risk of pre-eclampsia than non-
smokers

8. WORK-UP
Urine for proteinuria, Urinalysis and Urine Culture
RFTs & LFTs
CBC & P. Smear for schistocytes or helmet cells
LDH
Haemoconcentration (HCT inc. due to plasma leakage)
ECG
TSH (both hypo- and hyper- can cause HTN)
Rule out secondary causes esp. in non-obese women < 30 years with –ve Family
hx for HTN

9. WORK-UP CONTINUED…
Coagulation profile; PT, APTT & Fibrinogen levels are not affected
unless there is abruption, severe bleeding or severe liver
dysfunction.
Uric acid levels (Hyperuricemia…..reduced GFR, dec. tubular
secretion or inc. tubular reabsorption)
Troponins (pre-eclampsia is not associated with elevated troponin
levels in the absence of cardiac disease therefore trop I levels should
be done only when MI is suspected or EKG changes are observed)
High total cholesterol and TGs levels

10. RECOMMENDATIONS
When hypertension is diagnosed in a pregnant woman, the major issues are
establishing a diagnosis, deciding the blood pressure at which treatment should
be initiated and the target blood pressure, and avoiding drugs that may adversely
affect the fetus.
In contrast to nonpregnant individuals in whom blood pressure is staged as
normal, prehypertension, or stage 1 or 2, blood pressure in pregnant women is
either normal (<140/90 mmHg), mild to moderate hypertension (140 to 159/90 to
109 mmHg), or severe hypertension (≥160/110 mmHg).

11. Treatment of severe hypertension has a well-established maternal benefit of
reduction in stroke risk, but there is no proven maternal or foetal benefit from
treatment of mild to moderate hypertension over the relatively short duration of a
full-term pregnancy. In addition, lowering maternal blood pressure excessively
may be associated with decreased placental perfusion, and exposure of the fetus
to potentially harmful effects of medications.
ACEIs, ARBs, and direct renin inhibitors are contraindicated at all stages of
pregnancy.

14. MANAGEMENT…
• Preeclampsia
Avoid antihypertensive therapy for mild hypertension associated
with preeclampsia (Grade 2B). No proven benefits to mother or
fetus, other than reduction in risk of severe maternal hypertension,
and there are concerns about potential adverse fetal effects.
 Moderate hypertension is treated on a case-by-case basis, such as
in women with worrisome cerebrovascular symptoms or evidence of
target organ damage.

15. Uptodate recommend treatment of severe hypertension (Grade 1B).
The goal of treatment is to prevent Maternal cerebrovascular
complications.
Initiate antihypertensive therapy in adult women at systolic pressures
≥150 mmHg and diastolic blood pressures ≥100 mmHg.
Initiate treatment at a lower threshold in younger women whose baseline
blood pressure was low, and in those with symptoms that may be
attributable to elevated blood pressure (headache, visual disturbances,
chest discomfort).
ACOG, have recommended treatment of hypertension when systolic
blood pressure is ≥160 mm Hg.

16. For acute blood pressure therapy, intravenous labetalol (Grade 2B)
or hydralazine is recommended.
For patients receiving antihypertensive drugs, target blood pressure goal is
systolic pressure of 130 to 150 mmHg and diastolic pressure of 80 to 100 mmHg.
When to deliver?
Experts consistently recommend delivery of women with preeclampsia at ≥37
weeks of gestation, even in the absence of features of severe disease.
Pregnancies in which the fetus has not attained a viable gestational age,
pregnancies ≥34 weeks of gestation, and pregnancies in which the
maternal and/or fetal condition is unstable are not candidates for conservative
management.
Attempting to prolong pregnancy in these settings subjects the mother and fetus
to significant risks with relatively small potential benefits; therefore, delivery is
preferable.

17. TREATMENT OF GESTATIONAL HYPERTENSION
— The indications for and choice of antihypertensive therapy in women with
gestational hypertension are the same as for women with preeclampsia.
Timing of delivery — We recommend delivery at term for women with
gestational hypertension, in general agreement with guidelines from multiple
major societies .
 The optimum gestational age between 37 and 40 weeks for intervention
(induction, cesarean delivery) because of gestational hypertension is
controversial. We individualize these cases based on the degree of hypertension,
presence of comorbidities, and the presence of risk factors for adverse pregnancy
outcome.

18. For uncomplicated pregnancies with only an occasional blood
pressure ≥140/90 mmHg and <160/110 mmHg, we deliver at 38 to
39 weeks, since neonatal morbidity is lower than at 37 to 38 weeks .
For pregnancies with frequent blood pressures ≥140/90 mmHg
and <160/110 mmHg, comorbidities, or other risk factors for adverse
outcome, we deliver at 37 weeks.

19. CHRONIC (PRE-EXISTING) HYPERTENSION
For pregnant women with uncomplicated mild (140 to 150 / 90 to 100
mmHg) primary hypertension: UpToDate suggest not initiating
antihypertensive drug treatment (Grade 2B) and tapering and eventually
discontinuing antihypertensive drug treatment in women already on
therapy (Grade 2C), while closely monitoring the blood pressure
response.
There are no proven maternal or fetal benefits from therapy of mild
hypertension, other than a reduction in risk of developing severe
hypertension, and there is some concern about potential adverse effects
of treatment on fetal growth.

20. Uptodate initiate or resume antihypertensive therapy in pregnant women
with persistent systolic pressures ≥150 mmHg, diastolic pressures 95 to
99 mmHg, or in those with lower pressures and signs of hypertensive end-
organ damage (Grade 2C).
These thresholds allow non-emergency intervention with oral drugs while
hypertension is only moderately elevated. ACOG limit antihypertensive
drug treatment to pregnant women with severe hypertension (blood
pressure ≥160/110 mmHg), since there is consensus that intervention at
this level has a proven benefit of protecting the mother from serious
complications, such as stroke, heart failure, or renal failure.

21. Uptodate suggest antihypertensive therapy with
either methyldopa or labetalol (Grade 2B). A long-acting calcium channel blocker
(eg, nifedipine) can be added if needed.
Our treatment target is systolic pressure 130 to 150 mmHg and diastolic pressure
80 to 100 mmHg.
For pregnant women with complicated or secondary hypertension (eg, target-
organ damage [left ventricular hypertrophy, microalbuminuria, retinopathy],
dyslipidemia, maternal age over 40 years, history of stroke, previous perinatal
loss, diabetes), uptodate suggest treatment of hypertension, even if mild (Grade
2C). treatment target is systolic pressure 120 to 140 mmHg and diastolic
pressure 80 to 90 mmHg.

22. • Uptodate agrees with an expert consensus panel and the American College of
Obstetricians and Gynaecologists (ACOG) that suggested the following approach
for delivery of women with chronic hypertension and no superimposed
preeclampsia, fetal growth restriction, or abruption (past or current pregnancy):
• 38+0 to 39+6 weeks of gestation for women not requiring medication
• 37+0 to 39+6 weeks for women with hypertension controlled with medication
• 36+0 to 37+6 weeks for women with severe hypertension difficult to control
• The ranges allow for clinician judgment on a case-by-case basis, with
consideration of factors such as steady-state levels of and trends in blood
pressure, fetal growth and amniotic fluid volume, and cervical status.

23.  The National Institute for Health and Care Excellence (NICE) recommends that for pregnant women
with uncomplicated chronic hypertension the goal is to keep blood pressure lower than 150/100 mmHg . In
women with gestational hypertension or preeclampsia, treatment is initiated at blood
pressures ≥150/100 mmHg with the goal of systolic blood pressures <150 mmHg and diastolic blood
pressures of 80 to 100 mmHg. They also recommend use of low dose aspirin (75 mg/day) from 12 weeks
of gestation to reduce the risk of preeclampsia.
 The American College of Obstetricians and Gynecologists (ACOG) Task Force on Hypertension in
Pregnancy recommends treatment of persistent chronic hypertension when systolic pressure is ≥160
mmHg or diastolic pressure is ≥105 mmHg and suggests avoiding antihypertensive therapy in women with
blood pressures below this level and no evidence of end-organ damage . They
suggest labetalol, nifedipine, or methyldopa as first-line therapy. They also suggest avoiding angiotensin-
converting enzyme inhibitors, angiotensin receptor blockers, renin inhibitors, and mineralocorticoid receptor
antagonists. The goal of management is maintenance of blood pressures
between 120/80 and 160/105 mmHg.

24. • The ACOG Committee Opinion on emergent therapy of acute onset severe
hypertension in pregnancy and postpartum recommends treatment of acute
onset, severe systolic (≥160 mmHg) hypertension, severe diastolic (≥110 mmHg)
hypertension, or both to achieve a blood pressure of 140 to 150/90 to 100 mmHg
• They suggest labetalol, hydralazine, or oral nifedipine as first-line therapy and
provide explicit treatment guidelines for lowering blood pressure. They
recommend using the short-acting preparation of oral nifedipine, which in our
experience is associated with more symptomatic hypotension and headache
compared with the extended release preparation which has also been
successfully used in this setting

25. • Postpartum hypertension
• Blood pressure may be significantly higher in the immediate postpartum period
than antepartum or intrapartum. This may be due to preeclampsia, intrapartum
administration of intravenous fluids, loss of pregnancy associated vasodilation
after delivery, mobilization of extracellular fluid after delivery, administration of
non-steroidal anti-inflammatory agents for postdelivery analgesia, or
administration of ergot derivatives to treat postpartum hemorrhage.
• Treatment is indicated for persistent hypertension and consideration should be
given to initiating therapy well before levels reach the severe range, especially
since concerns regarding placental perfusion are no longer relevant.

26. • Evaluation — Women with new onset postpartum hypertension should be
evaluated by history (including review of postpartum medications and fluid
balance), physical examination, and laboratory studies (liver chemistries, platelet
count, creatinine, urine protein). The presence of neurologic, cardiac, or
gastrointestinal symptoms or laboratory abnormalities suggests a disorder other
than transient hypertension related to fluids and/or medications .
• Management — Antihypertensive agents should be administered to women with
persistent postpartum hypertension. The majority of pregnancy-related strokes
occur in the first 10 days after delivery and typically within 48 hours postpartum,
with hypertension the strongest risk factor . Evidence to guide optimum
management of postpartum hypertension is limited.

27. Uptodate recommend not using NSAIDs in women with postpartum hypertension.
Although the overall risk of increasing blood pressure or causing persistent blood
pressure elevation appears to be low, hypertensive crises have been reported.
We also recommend initiating oral antihypertensive therapy if blood pressures are
persistently greater than 140 mmHg systolic at the time of discharge from the
hospital.
Medications similar to those used in pregnancy are often used postpartum, since
most are compatible with breastfeeding. If additional agents are required and the
woman is breastfeeding, it is advisable to consult with a pediatrician or other
authority. One guideline suggests avoiding methyldopa postpartum because of the
risk of postnatal depression.

28. • Brief furosemide therapy (20 mg orally once or twice per day for five days) may
facilitate return to normotension in women with severe hypertension, especially if
accompanied by debilitating oedema; however, the use of diuretics in this setting has
not been studied extensively. In breastfeeding women, furosemide is avoided unless
prompt maternal diuresis is essential.
• In women with chronic hypertension, antihypertensive drugs should be continued or
the prepregnancy regimen resumed after delivery, with consideration of safety in
breastfeeding and dosage adjustments to reflect the decrease in volume of
distribution and glomerular filtration rate that occurs after delivery . Although rare,
strokes associated with pregnancy (both hemorrhagic and thrombotic) are more likely
to occur in the postpartum period ; thus persistent hypertension should not be
ignored.

29. DISCHARGE PLANNING
 For women not on any anti-hypertensive medication, if blood pressures are
borderline prior to discharge, blood pressures should be followed closely after
discharge; home blood pressure monitoring is useful, if possible. Women should
be advised to seek medical attention if they develop severe headaches or if blood
pressure increases to severe levels.
 Blood pressure should also be monitored closely in women on anti-hypertensive
medication to avoid hypotension as the woman's blood pressure returns to her
normal baseline level. If prepregnancy blood pressure was normal and the patient
is not hypertensive on medication, it is reasonable to stop the antihypertensive
agent after three weeks and monitor blood pressure to assess whether further
treatment is indicated.