1. Hypertension in Pregnancy
นพ.สิทธิพงศ์ ถวิลการ
กลุ่มงานสูตินรีเวชกรรม รพ.ขอนแก่น

2. Prediction and prevention
Contents
Classification HT In
Pregnancy
Pathogenesis and Risk factors
Diagnosis
Prediction and prevention
Management

3. Introduction
Hypertensive disorders of pregnancy remain a major health issue for women and their infants worldwide
The ACOG convened a task force of experts in the management of HT in pregnancy to review available data and publish evidence-based recommendations for clinical practice
Preclampsia is a dynamic process, by nature is progressive

4. Classification Preeclampsia-eclampsia: Chronic hypertension
BP elevation after 20 weeks of gestation with proteinuria or any of the severe features of preeclampsia
Chronic hypertension
BP elevation before 20 weeks of gestation or before pregnancy
Chronic hypertension with superimposed preeclampsia
Gestational hypertension :
evidence for the preeclampsia not develop and HT resolves by 12 weeks postpartum

5. Previous classification

6. Classification Avoid use of term mild preeclampsia
>> replace with preeclampsia without severe features
Severe preeclampsia
>> preeclampsia with severe features

7. Abnormal trophoblastic invasion
Pathogenesis
Abnormal trophoblastic invasion 
Endothelial cell
injury
Pathogenesis of
Preeclampsia
Genetic
factors
Vasospasm

8. Pathophysiology

9. Risk factors Young and Nulliparous Obesity Multifetal gestation
4.3% in BMI < 20
13.3 % in BMI > 35
Twins 13% vs Singleton 5%
Young and
Nulliparous
Obesity
Multifetal gestation
Incidence 3-10%
Older women : Chronic HT with superimposed precclampsia
Previous
Preeclampsia

10. Diagnosis : Preeclampsia

12. Diagnosis : Preeclampsia with severe feature

13. Diagnosis : Preeclampsia with severe feature
The diagnosis of severe preeclampsia is no longer dependent on the presence of proteinuria
Do not delay management of preeclampsia in the absence of proteinuria
Massive proteinuria (> 2 g) has been eliminated from consideration of preeclampsia as severe
Fetal growth restriction has been removed as a finding indicative of severe preeclampsia

14. Prediction of preeclampsia
Screening to predict preeclampsia beyond obtaining an appropriate medical history to evaluate for risk factors is not recommended
TVS of a cervix and funneling

15. Prevention of preeclampsia
Antioxidants: vitamins C and E are not effective.
Calcium: may be useful in populations with low calcium intake (not in the USA).
Low-dose aspirin (60 to 80 mg/day): beginning in the late first trimester may have slight effect to reduce preeclampsia and adverse perinatal outcomes.
>> suggest in women with Hx of early onset preeclampsia and preterm delivery less than 34 wks or preeclampsia in more than one prior pregnancy
Bed rest or salt restriction: no evidence of benefit.
TVS of a cervix and funneling

16. Basic management objective Current clinical issues
Termination of pregnancy with the least possible trauma to mother and fetus
Birth of infants who subsequently thrives
Complete retroration of health to mother
Early diagnosis of preeclampsia
Precise gestational age
Important
Current clinical issues
Timing of delivery
Antihypertensive drugs
Magnesium sulfate

17. Management Hospitalization for women with new onset HT
Daily assessment of maternal symptoms, weight gain and fetal movement
Analysis for proteinuria
BP every 4 hours
Measurement of serum Cr, Hepatic enzymes, CBC (some recommend uric acid, LDH, coagulogram)
Evaluation of fetal size, amniotic volume, well-being

18. Management Timing of delivery :
Preeclampsia without severe features; 37 weeks
Severe preeclampsia ;
< 34 weeks of gestation with stable maternal and fetal conditions, it is recommended that continued pregnancy be undertaken only at facilities with adequate maternal and neonatal intensive care resources
≥ 34 weeks of gestation, and in those with unstable maternal or fetal conditions irrespective of gestational age, delivery soon after maternal stabilization is recommended
Chronic hypertension; 38 weeks

19. Management

20. Management

21. Management Antihypertensive drugs ;
preeclampsia with severe hypertension during pregnancy (sustained systolic BP of at least 160 or diastolic of at least 110)
persistent chronic hypertension with systolic BP of at least160 or diastolic BP of at least105

22. Management Antihypertensive drugs ; IV labetalol
• bolus doses mg (max 300/hr)
• continuous IV infusion (1-2 mg/min)
IV bolus doses of hydralazine
• 5, 10, 10 mg q 20 min (max 25 mg)
Oral nifedipine
• mg q 20 min (max 60 mg)
IV Sodium nitroprusside

23. Management Magnesium sulfate prevent seizure;
Preeclampsia without severe feature do not need magnesium sulfate
(risk for eclampsia = 1/100)

24. Management : MgSO4 dosage

25. Management : MgSO4 dosage

26. TASK FORCE RECOMMENDATIONS
Close monitoring of women with gestational HT or preeclampsia without severe features with
serial assessment of maternal symptoms and fetal movement (daily by the woman)
serial measurements of BP (twice weekly)
assessment of platelet counts and liver enzymes (weekly) is suggested
US to assess fetal growth and antenatal testing to assess fetal status
If evidence of fetal growth restriction is found in, fetoplacental assessment that includes umbilical artery Doppler velocimetry as an adjunct antenatal test is recommended

27. TASK FORCE RECOMMENDATIONS
For women with preeclampsia, it is suggested that a delivery decision should not be based on the amount of proteinuria or change in the amount of proteinuria
For women with preeclampsia, it is suggested that the mode of delivery need not be cesarean delivery. The mode of delivery should be determined by fetal gestational age, fetal presentation, cervical status, and maternal and fetal conditions

28. TASK FORCE RECOMMENDATIONS
For women with HELLP syndrome;
before the gestational age of fetal viability, it is recommended that delivery be undertaken shortly after initial maternal stabilization
≥34 weeks of gestation, it is recommended that delivery be undertaken soon after initial maternal stabilization
gestational age of fetal viability to <34 weeks of gestation, it is suggested that delivery be delayed for hours if maternal and fetal conditions remain stable to complete a course of corticosteroids for fetal benefit

29. TASK FORCE RECOMMENDATIONS
Post partum period;
BP be monitored in the hospital or that equivalent outpatient surveillance be performed for at least 72 hours postpartum and again 7-10 days after delivery or earlier in women with symptoms
discharge instructions include information about the signs and symptoms of preeclampsia as well as the importance of prompt reporting of this information to their health care providers

30. TASK FORCE RECOMMENDATIONS
Post partum period;
new-onset hypertension associated with headaches or blurred vision or preeclampsia with severe hypertension, the parenteral administration of magnesium sulfate is suggested
persistent postpartum hypertension, BP of 150 systolic or 100 diastolic or higher, on at least two occasions that are at least 4-6 hours apart, antihypertensive therapy is suggested
Persistent BP of 160 systolic or 110 diastolic or higher should be treated within 1 hour

31. References
American College of Obstetricians and Gynecologists: Hypertension in pregnancy Executive summary, November 2013
Williams Obstetrics, 24ed 

32. Thank You For Your Attention !