Chronic hypertension in pregnancy is now considered mild if blood pressures do not exceed 159 mmHg systolic and 109 mmHg diastolic and severe if pressures are ≥ 160 mmHg systolic or 110 mmHg diastolic, although controversy also exists as to the most appropriate cutoffs for this definition.Because chronic hypertension can progress to more severe forms of disease, it is important to accurately diagnose the condition early, ideally prior to pregnancy, and initiate management to control parental blood pressure. This is often difficult, as many reproductive individuals may not regularly visit the doctor and, when pregnant, may initially present for prenatal care in the second trimester. Pre-eclampsia and eclampsia
Preeclampsia is a medical condition which usually develops after 20 weeks of gestation and traditionally involves both newly increased blood pressure (blood pressure > 140/90 mmHg) and proteinuria. Preeclampsia is a leading cause of fetal complications, which include low birth weight, preterm birth, and stillbirth. Women with preeclampsia are encouraged to deliver the child after 37 weeks of gestation to minimize the risks of the severe complications.Preeclampsia can also be diagnosed if a woman has both increased blood pressure and 1 or more signs of significant organ damage. Signs of significant organ damage include:
Severely elevated blood pressure (blood pressure > 160/110)
Thrombocytopenia
Increased or rapidly elevating levels of creatinine in the blood
Increased liver enzymes
Pulmonary edema
New or persistent headaches that do not respond to pain medication
Blurred or altered visionIf a woman with preeclampsia has any of these signs of significant organ damage, then her condition is classified as preeclampsia with severe features.
Management
According to one review published in 2003, reduction of the blood pressure by 5 mmHg can decrease the risk of stroke by 34%, of ischemic heart disease by 21%, and reduce the likelihood of dementia, heart failure, and mortality from cardiovascular disease. Target blood pressure
Various expert groups have produced guidelines regarding how low the blood pressure target should be when a person is treated for hypertension. These groups recommend a target below the range 140–160 / 90–100 mmHg for the general population. Cochrane reviews recommend similar targets for subgroups such as people with diabetes and people with prior cardiovascular disease. Additionally, Cochrane reviews have found that for older individuals with moderate to high cardiovascular risk, the benefits of trying to achieve a lower than standard blood pressure target (at or below 140/90 mmHg) are outweighed by the risk associated with the intervention. These findings may not be applicable to other populations.Many expert groups recommend a slightly higher target of 150/90 mmHg for those over somewhere between 60 and 80 years of age. The JNC-8 and American College of Physicians recommend the target of 150/90 mmHg for those over 60 years of age, but some experts within these groups disagree with this recommendation. Some expert groups have also recommended slightly lower targets in those with diabetes or chronic kidney disease with protein loss in the urine, but others recommend the same target as for the general population.