High Blood Pressure in Pregnancy
Current Guidance Update
First-Line Antihypertensive
Labetalol is the recommended first-line antihypertensive medication during pregnancy, while nifedipine and methyldopa remain suitable alternatives.
Hypertensive Disorders
Hypertensive disorders in pregnancy are classified into chronic hypertension, gestational hypertension, preeclampsia, and white coat hypertension.
Low-Dose Aspirin
Starting low-dose aspirin between 12–16 weeks reduces the risk of preterm preeclampsia by approximately 62% in high-risk women identified by first-trimester combined screening.
Magnesium Sulphate
Magnesium sulphate remains the drug of choice for both seizure prophylaxis and treatment in women with eclampsia.
Introduction
Hypertensive Disorders in Pregnancy
Classification
Hypertension in pregnancy is defined as systolic BP ≥140 mmHg and/or diastolic BP ≥90 mmHg on two occasions at least 4 hours apart. ISSHP classifies disorders into chronic hypertension, gestational hypertension, preeclampsia, eclampsia and HELLP syndrome.
Preeclampsia Pathophysiology
Preeclampsia is a placental disorder caused by abnormal trophoblast invasion, leading to systemic endothelial dysfunction, hypertension, proteinuria and multi-organ involvement. It affects approximately 3–5% of pregnancies worldwide.
Global Impact
Early identification and monitoring reduce maternal and fetal complications, making routine antenatal screening and specialist care essential throughout pregnancy.
First-Trimester Screening & Aspirin Prophylaxis
The FMF first-trimester combined screening model identifies approximately 90% of women who will develop preterm preeclampsia.
Low-dose aspirin (150mg), started between 11–16 weeks and continued until 36 weeks, reduces the incidence of preterm preeclampsia by approximately 62% in high-risk pregnancies.
Diagnosis of Preeclampsia
Proteinuria
Acute Kidney Injury
Thrombocytopenia
Impaired Liver Function
Neurological Complications
Pulmonary Oedema
Uteroplacental Dysfunction
New-Onset Hypertension After 20 Weeks
Management & Postpartum Hypertension
Management
First-line antihypertensives are labetalol, nifedipine, and methyldopa; target BP for treated hypertension is 135/85 mmHg.
Severe preeclampsia requires intensive monitoring including frequent blood pressure checks, daily urinalysis, twice-weekly blood tests, and regular fetal assessment.
Delivery is the only definitive treatment; antenatal corticosteroids are given if delivery before 35 weeks is anticipated, and magnesium sulphate is administered for seizure prophylaxis in severe disease.
Postpartum Hypertension
Blood pressure frequently worsens in the first 5 days postpartum.
Continued monitoring and antihypertensive treatment for up to 6 weeks post-delivery is essential, with urgent assessment required for severe headache, visual changes, or epigastric pain.
Frequently Asked Questions
How is preeclampsia different from gestational hypertension?
Gestational hypertension is high blood pressure alone; preeclampsia involves high blood pressure plus evidence of organ damage, carrying significantly higher risk.
Can preeclampsia be prevented?
First-trimester screening followed by aspirin prophylaxis in high-risk women reduces preterm preeclampsia risk by approximately 62%.
Will I get preeclampsia again in future pregnancies?
Recurrence risk is approximately 16%, higher for early-onset disease. Screening and aspirin prophylaxis should be offered in subsequent pregnancies.
Conclusion
Hypertensive disorders of pregnancy, and preeclampsia in particular, remain leading causes of maternal and perinatal morbidity. Evidence-based screening, prophylaxis, prompt diagnosis, and structured management are essential to reducing this burden.
Sources & References
This article draws on guidance current at the time of writing from the following bodies and publications:
- NICE NG133 (updated 2023)
- ISSHP (2022) Classification
- FIGO (2023)
- ACOG (2024 Practice Bulletin #222)
General reference bodies for women's health guidance:
RCOG
rcog.org.ukACOG
acog.orgFIGO
figo.orgWHO
who.intNICE
nice.org.uk⚠ IMPORTANT DISCLAIMER
This article is provided for general knowledge and reference purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. No medication, treatment, or change to your healthcare should be undertaken based on this content without first consulting a qualified doctor. Always seek the advice of your physician or another qualified health provider with any questions you may have regarding a medical condition.
Consult Dr. Ruby Rashmi
Specialist Obstetrician & Gynecologist, Dubai
