Accurately pinpointing particular risk factors has stifled researchers because of the varied nature of Hypertensive disorders of pregnancy.
[7] Chronic poorly-controlled high blood pressure before and during pregnancy puts a pregnant woman and her baby at risk for problems.
It is associated with an increased risk for maternal complications such as preeclampsia, placental abruption (when the placenta separates from the wall of the uterus), and gestational diabetes.
Other symptoms that seem to occur with preeclampsia include persistent headaches, blurred vision or sensitivity to light, and abdominal pain.
[7] A classification of hypertensive disorders of pregnancy uses 4 categories as recommended by the U.S. National High Blood Pressure Education Program Working Group on High Blood Pressure in Pregnancy:[10] This terminology is preferred over the older but widely used term pregnancy-induced hypertension (PIH) because it is more precise.
[10] The newer terminology reflects simply relation of pregnancy with either the onset or first detection of hypertension; the question of causation, while pathogenetically interesting, is not the important point for most health care purposes.
[11] 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.
[12] 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.
Women with preeclampsia are encouraged to deliver the child after 37 weeks of gestation to minimize the risks of the severe complications.
Preeclampsia is usually characterized by elevated blood pressure and frequently protein in the urine after the 20th week of pregnancy, believed to be caused by abnormal placental growth leading to endothelial dysfunction and inflammation.
Unusual levels of this angiogenic factor and others have displayed potential in forecasting preeclampsia, which could enable earlier intervention and monitoring methods.
Furthermore, scientists are studying lifestyle elements such as diet and physical activity to evaluate their possible impact on decreasing HDP risk, even though definite conclusions have not been made.
[13] Eclampsia is one particularly concerning form of preeclampsia in which a pregnant woman who previously presented with signs of newly increased blood pressure begins to experience new generalized seizures or coma.
[19] Like ordinary pre-eclampsia, superimposed pre-eclampsia can also occur with severe features, which are defined as: systolic blood pressure ≥160 mmHg or diastolic blood pressure ≥110 mmHg despite escalation of antihypertensive therapy; thrombocytopenia (platelet count <100,000/microL); impaired liver function; new-onset or worsening renal insufficiency; pulmonary edema; or persistent cerebral or visual disturbances.
Certain medications may not be ideal for blood pressure control during pregnancy such as angiotensin-converting enzyme (ACE) inhibitors and angiotensin II (AII) receptor antagonists.
[20] There is limited evidence to suggest that calcium supplementation may reduce the risk of pre-eclampsia or stillbirth but it is unclear if it has other benefits.
[21] Current research is focused on enhancing early identification, exploring genetic and environmental factors, and creating novel therapies.
The exact timing of when to induce labor is dependent on the severity of symptoms related to the hypertensive disease, as well as the medical condition of both the mother and the fetus.
[12] Women with chronic hypertension in pregnancy must be closely monitored because they are five times as likely as those with normal blood pressure to develop pre-eclampsia, which is a much more severe condition with serious risks for the mother and fetus.
[13] Treatment should be continued from the time of diagnosis to several weeks postpartum given the increased risk of medical complications immediately following delivery of the fetus.
[7] Women who have chronic hypertension before their pregnancy are at increased risk of complications such as premature birth, low birthweight or stillbirth.
Obtaining early and regular prenatal care for pregnant women is important to identify and treat blood pressure disorders.
[7] Although the proportion of pregnancies with gestational hypertension and eclampsia has remained about the same in the U.S. over the past decade, the rate of preeclampsia has increased by nearly one-third.
This increase is due in part to a rise in the numbers of older mothers and of multiple births, where preeclampsia occurs more frequently.