O13.2 Gestational [pregnancy-induced] hypertension without significant proteinuria, second trimester

Name of the Condition

• Gestational [pregnancy-induced] hypertension without significant proteinuria, second trimester (O13.2)

Summary

Gestational hypertension without significant proteinuria in the second trimester is a pregnancy-related blood pressure elevation occurring after 20 weeks of gestation, characterized by systolic blood pressure ≥140 mmHg or diastolic blood pressure ≥90 mmHg on two occasions at least 4 hours apart, without substantial proteinuria. This condition is distinct from chronic hypertension and requires monitoring to assess progression or resolution.

Causes

The exact cause is not fully understood, but it is thought to involve placental and vascular factors that disrupt normal pregnancy physiology. Contributing mechanisms may include abnormal placental implantation, endothelial dysfunction, and imbalances in vasoactive substances, leading to increased vascular resistance and elevated blood pressure.

Risk Factors

• First pregnancy (nulliparity).
• Advanced maternal age (over 35 years).
• Pre-existing conditions like chronic hypertension, diabetes, or renal disease.
• Family history of preeclampsia or gestational hypertension.
• Obesity (BMI ≥30).
• Multiple gestation (twins or more).

Symptoms

• Elevated blood pressure (≥140/90 mmHg) without significant proteinuria.
• Possible mild headaches, visual changes, or epigastric pain.

Diagnosis

Diagnosis involves confirming blood pressure elevation after 20 weeks of gestation without significant proteinuria. Blood pressure measurements are taken on two separate occasions at least 4 hours apart. Urine tests assess for proteinuria, and other conditions like chronic hypertension or preeclampsia are ruled out.

Treatment Options

• Monitoring: Regular blood pressure checks and urine protein tests to track progression.
• Lifestyle modifications: Rest, reduced sodium intake, and avoidance of alcohol.
• Medication: Antihypertensives may be prescribed if blood pressure is severely elevated.
• Delivery planning: If hypertension persists or worsens, delivery may be induced or scheduled based on gestational age and maternal-fetal health.

Prognosis and Follow-Up

Most cases resolve after delivery, but some may progress to preeclampsia or chronic hypertension. Close follow-up is necessary to monitor blood pressure and proteinuria. Postpartum care includes checking blood pressure within 7-10 days and at 6 weeks to ensure resolution.

Complications

• Progression to preeclampsia or eclampsia.
• Increased risk of preterm birth or low birth weight.
• Placental abruption or fetal growth restriction in severe cases.

Lifestyle & Prevention

• Maintain a healthy weight before pregnancy.
• Follow a balanced diet low in sodium.
• Avoid smoking and limit caffeine.
• Attend all prenatal appointments for regular monitoring.

When to Seek Professional Help

Seek immediate care if blood pressure rises significantly, or if symptoms like severe headache, vision changes, or abdominal pain occur, as these may indicate progression to a more serious condition.

Tips for Medical Coders

Document the timing (second trimester), blood pressure measurements, and absence of significant proteinuria. Ensure the diagnosis is confirmed after 20 weeks of gestation and differentiate from chronic hypertension or preeclampsia. Include details on monitoring and any interventions provided.