Pregnancy induced hypertension

Pregnancy-induced hypertension
Synonyms	Gestational hypertension
Pronounce	N/A
Specialty	N/A
Symptoms	High blood pressure during pregnancy
Complications	Preeclampsia, eclampsia, preterm birth, placental abruption
Onset	After 20 weeks of pregnancy
Duration	Until delivery
Types	N/A
Causes	Unknown
Risks	First pregnancy, multiple gestation, obesity, age over 35
Diagnosis	Blood pressure measurement, urine tests
Differential diagnosis	N/A
Prevention	N/A
Treatment	Monitoring, medication, delivery
Medication	N/A
Prognosis	N/A
Frequency	6-8% of pregnancies
Deaths	N/A

Pregnancy-induced hypertension (PIH), also known as gestational hypertension, is a condition characterized by high blood pressure during pregnancy. It typically occurs after 20 weeks of gestation in women who previously had normal blood pressure. PIH is a significant concern in obstetrics due to its potential to progress to more severe conditions such as preeclampsia and eclampsia.

Pathophysiology

The exact cause of pregnancy-induced hypertension is not well understood. It is believed to involve abnormal placentation, leading to poor placental perfusion and the release of factors that cause widespread endothelial dysfunction. This dysfunction results in increased vascular resistance and hypertension. The condition is also associated with an imbalance between angiogenic and anti-angiogenic factors in the maternal circulation.

Risk Factors

Several risk factors have been identified for pregnancy-induced hypertension:

• Primigravida (first pregnancy)
• Multiple gestation (e.g., twins or triplets)
• Obesity
• Maternal age over 35 years
• Family history of hypertension or preeclampsia
• Pre-existing medical conditions such as diabetes mellitus or chronic hypertension

Clinical Presentation

Pregnancy-induced hypertension is diagnosed when a pregnant woman develops a systolic blood pressure of 140 mmHg or higher, or a diastolic blood pressure of 90 mmHg or higher, on two separate occasions at least four hours apart, after 20 weeks of gestation. Unlike preeclampsia, PIH is not associated with significant proteinuria or organ dysfunction.

Diagnosis

The diagnosis of pregnancy-induced hypertension is primarily based on blood pressure measurements. Additional tests may include:

• Urinalysis to rule out significant proteinuria
• Blood tests to assess liver function, kidney function, and platelet count
• Fetal ultrasound to monitor fetal growth and amniotic fluid levels

Management

The management of pregnancy-induced hypertension involves close monitoring of both the mother and the fetus. Key aspects include:

• Regular blood pressure monitoring
• Lifestyle modifications such as reduced salt intake and increased rest
• Antihypertensive medications, if necessary, to control blood pressure
• Frequent prenatal visits to monitor fetal well-being
• Early delivery if the condition progresses to preeclampsia or if there are signs of fetal distress

Complications

If left untreated, pregnancy-induced hypertension can lead to several complications, including:

• Preeclampsia: Characterized by hypertension and significant proteinuria, potentially leading to organ dysfunction
• Eclampsia: The onset of seizures in a woman with preeclampsia
• Preterm birth: Delivery before 37 weeks of gestation
• Placental abruption: Premature separation of the placenta from the uterine wall

Prognosis

With appropriate management, most women with pregnancy-induced hypertension can have a successful pregnancy outcome. However, they are at increased risk for developing hypertension in future pregnancies and later in life.

Prevention

While there is no guaranteed way to prevent pregnancy-induced hypertension, some strategies may reduce the risk:

• Regular prenatal care
• Maintaining a healthy weight before and during pregnancy
• Managing pre-existing medical conditions
• Avoiding smoking and alcohol

See Also

• Preeclampsia
• Eclampsia
• Chronic hypertension
• Obstetrics