Chronic Hypertension in Pregnancy: New Concepts for Classification and Management

Abstract

Chronic hypertension in pregnancy is traditionally classified according to degree of blood pressure (BP) elevation. Alternatively, stratifying women as high or low risk based on the etiology of hypertension, baseline work-up, and comorbid medical conditions will better inform clinicians about thresholds to initiate antihypertensive therapy, target BPs, frequency of antepartum visits, and timing of delivery. Women classified as high-risk chronic hypertension as described here require stricter BP management and more frequent follow-up visits as their associated rates of adverse maternal and/or fetal/neonatal outcomes appear higher than women classified as low-risk chronic hypertension. The latter group can in most cases be managed similarly to the general obstetric population.

Management of hypertension in pregnancy — prevention, diagnosis, treatment and long-term prognosis. A position statement of the Polish Society of Hypertension, Polish Cardiac Society and Polish Society of Gynaecologists and Obstetricians

“…• BP > 160/110 mm Hg in the first trimester; • HT duration of 5 or more years; • HT treated with 2 or more medications; • history of obstetric complications (PE, premature placental abruption); • chronic diseases: left ventricular dysfunction, retinopathy, lipid disorders, microangiopathy, stroke, diabetes, chronic kidney disease, connective tissue diseases or the presence of lupus anticoagulant [13]. Pregnant women with these risk factors are more likely to develop rare life-threatening complications, including hypertensive encephalopathy, pulmonary oedema, retinopathy, intracerebral haemorrhage or acute kidney injury [53].…”

“…Hypertension promotes low birth weight (LBW), increases the risk of PE superimposed on chronic HT and preterm birth, may cause placental abruption, leads to complications which require prolonged intensive care of a neonate with specialist neonatal treatment, and may cause intrauterine foetal death [12,13].…”

“…PE is associated with a particularly high risk of complications harmful to the mother and foetus. Each year, PE causes over 500 thousand foetal and neonatal deaths and over 70 thousand maternal deaths worldwide [1,12,13].Developing recommendations on the management of HT in pregnancy is challenging for two reasons -first, the number of studies, especially with prospective and randomized design, is limited, and second, approved indications and registry data limit the possibility to develop recommendations regarding drug classes. It is only possible to comment on the potential use of selected drugs [1, 2, 4,9,11].Most guidelines and recommendations published to date have been developed separately by societies of cardiology/hypertension or by societies of obstetrics and gynaecology [1][2][3][4][5][6][7][8][9].…”

“…PE is associated with a particularly high risk of complications harmful to the mother and foetus. Each year, PE causes over 500 thousand foetal and neonatal deaths and over 70 thousand maternal deaths worldwide [1,12,13].…”

Assessment of maternal deaths due to chronic hypertension: Lessons to learn – a ‘red flag’ for maternal and fetal complications

“…This could be chronic hypertension, but it can only be confirmed after the puerperium, although it may take up to 12 weeks post partum. [6] To avoid this, all women planning a pregnancy should attend a preconception clinic or visit a healthcare professional to exclude diseases such as hypertension or diabetes and optimise their disease condition before becoming pregnant. [6] High BP levels in pregnancy are usually regarded as mild (systolic 140 -159 mmHg, and/or diastolic 90 -109 mmHg), or severe (systolic >160 mmHg and/or diastolic >110 mmHg).…”