What is the next step in managing a 38-39 week pregnant primigravida (first-time mother) with hypertension (blood pressure 160/100 mmHg), who is in labor with a cervical dilation of 5 cm after 4 hours, and has a normal cardiotocography (CTG) and maternal condition?

Management of Primigravida with Severe Hypertension and Slow Labor Progress

This patient requires immediate blood pressure control with antihypertensive medication and amniotomy to augment labor, not simple reassessment or discharge—the answer is B (Amniotomy), but only after initiating urgent antihypertensive treatment.

Critical First Priority: Urgent Blood Pressure Management

This patient has severe hypertension (160/100 mmHg meets the ≥160/110 threshold) that requires immediate treatment within 15 minutes regardless of symptoms 1, 2. The absence of complaints does not eliminate stroke risk.

Immediate antihypertensive options:

• Oral nifedipine 10-20 mg, repeat in 30 minutes if needed (first-line intrapartum option) 1
• IV labetalol 20 mg bolus with escalating doses as alternative 1, 2
• Target BP: maintain <160/110 mmHg throughout labor 1, 2

Critical pitfall to avoid: Never delay antihypertensive treatment while waiting for proteinuria results or other labs—severe hypertension requires urgent treatment regardless 1.

Mandatory Urgent Laboratory Assessment

While treating BP, obtain:

• Hemoglobin, platelet count, liver transaminases, creatinine, and uric acid 1
• Urine protein quantification (24-hour collection or protein/creatinine ratio ≥30 mg/mmol is abnormal) 1
• These determine if preeclampsia is present and guide magnesium sulfate prophylaxis decisions

Labor Management Strategy: Active Augmentation Required

Why reassessment alone (Option A) is insufficient:

• Reassessing after 2 hours alone is inadequate given the severe hypertension requiring expedited delivery 1
• This primigravida has progressed only 1 cm in 4 hours (from 4 to 5 cm), indicating slow labor progress
• Early intervention with oxytocin and amniotomy for prevention and treatment of slow labor is recommended 3

Why amniotomy (Option B) is appropriate:

• Amniotomy combined with oxytocin augmentation is recommended to shorten time to delivery for women making slow progress 3
• At 38-39 weeks with severe hypertension, expedited delivery is beneficial 1, 2
• CTG remains reassuring, making vaginal delivery the preferred route

Why cesarean section (Option C) is premature:

• Vaginal delivery should be considered for women with hypertensive disorders unless cesarean is required for standard obstetric indications 2
• Cesarean for arrest should not be performed unless labor has arrested for minimum 4 hours with adequate uterine activity or 6 hours with inadequate uterine activity in a woman with ≥6 cm dilation 3
• This patient is only at 5 cm and has not yet received augmentation

Why discharge (Option D) is dangerous:

• Never discharge a patient with severe hypertension in active labor—this poses immediate maternal risk for stroke and eclampsia 1, 2

Additional Critical Management Steps

Magnesium sulfate consideration:

• Should be considered if preeclampsia is confirmed, especially with proteinuria and severe hypertension 1
• Loading dose: 4-5g IV over 3-4 minutes, maintenance 1-2g/hour 1
• Avoid concurrent use with calcium channel blockers due to precipitous hypotension risk 1

Monitoring requirements:

• CTG monitoring should continue throughout labor 1
• Blood pressure monitoring every 15-30 minutes during active management 1
• Fluid restriction to 60-80 mL/hour to prevent pulmonary edema 1

Algorithmic Approach for This Patient

1. Immediately administer antihypertensive (nifedipine 10-20 mg PO or labetalol 20 mg IV)
2. Obtain urgent labs (CBC, liver enzymes, creatinine, urine protein)
3. Perform amniotomy to augment labor progression
4. Initiate oxytocin augmentation if contractions remain inadequate
5. Start magnesium sulfate if labs confirm preeclampsia
6. Continue monitoring BP every 15-30 minutes, continuous CTG
7. Proceed with vaginal delivery unless standard obstetric indications for cesarean develop

The correct answer is B (Amniotomy), but this must be preceded by immediate antihypertensive treatment and accompanied by oxytocin augmentation and close monitoring.