What can a primigravida (first-time pregnant woman) with a family history of preeclampsia do to reduce her risk of developing the condition?

Preeclampsia Risk Reduction in Primigravida with Family History

For a primigravida with a maternal history of preeclampsia, calcium supplementation (1.5-2 g/day) is recommended if her dietary calcium intake is low (<600-800 mg/day), making option B the correct answer. 1

Primary Prevention Strategy

The most critical intervention is low-dose aspirin (75-162 mg daily) started before 16 weeks of gestation and continued until 36-37 weeks, which reduces preterm preeclampsia risk by approximately 62%. 1, 2, 3 A family history of preeclampsia (mother or sister) is recognized as a moderate risk factor that warrants aspirin prophylaxis. 1

Aspirin Dosing Specifics:

• Optimal dose: 100-150 mg daily (some guidelines recommend up to 162 mg) 1
• Timing: Must start before 16 weeks gestation (ideally at 12 weeks) 1, 2
• Duration: Continue until 36-37 weeks or delivery 1

Calcium Supplementation Guidelines

Calcium is indicated specifically for women with low dietary calcium intake (<600-800 mg/day):

• Dose: 1.5-2 g elemental calcium daily 1
• Alternative lower dose: 1-1.2 g daily minimum 1
• Mechanism: Reduces preeclampsia risk by 36-64% in populations with low baseline calcium intake 1, 4

The evidence shows calcium supplementation is most effective in women with low dietary calcium (<600 mg/day), reducing preeclampsia risk substantially (RR 0.36,95% CI 0.20-0.65). 4 For women who are calcium-replete, the benefit is less clear. 1

Important Calcium Administration Details:

• Calcium carbonate in divided doses ≤500 mg elemental calcium per dose for optimal absorption 5
• Benefits substantially outweigh risks, including the rare occurrence of HELLP syndrome 5, 4

Why Not Excessive Water Restriction (Option A)

Avoiding excessive water intake is NOT recommended for preeclampsia prevention. 1 In fact, guidelines specifically advise:

• Normal diet without salt restriction is recommended, particularly close to delivery 1
• Salt restriction may induce low intravascular volume, which is counterproductive 1
• There is no evidence that water restriction prevents preeclampsia

Additional Risk Assessment Considerations

This primigravida has two moderate risk factors (first pregnancy + family history), which meets criteria for aspirin prophylaxis in most guidelines. 1 Other factors to assess include:

• Maternal age >40 years 1
• BMI >35 kg/m² 1
• Multiple pregnancy 1
• Pregnancy interval >10 years (if applicable to future pregnancies) 1

Comprehensive Prevention Algorithm

For this patient, implement the following:

1. Start low-dose aspirin 100-150 mg daily before 16 weeks gestation 1, 2

2. Assess dietary calcium intake:

   • If <600-800 mg/day: Add calcium supplementation 1.5-2 g/day 1
   • If adequate intake: Calcium supplementation may not provide additional benefit 1

3. Encourage regular exercise: 50 minutes, 3 times weekly (combination of aerobic, strength, and flexibility training) 1

4. Monitor blood pressure at every prenatal visit 2

5. Avoid vitamin C and E supplementation (may worsen outcomes) 1

Common Pitfalls to Avoid

• Starting aspirin after 16 weeks significantly reduces effectiveness 1
• Recommending calcium to all women regardless of dietary intake (benefit is primarily in low-calcium populations) 1, 4
• Advising water or salt restriction (not evidence-based and potentially harmful) 1
• Using high-dose vitamin supplementation (vitamin C and E are associated with worse outcomes) 1

Long-term Counseling

Women with family history of preeclampsia should understand their approximately 15% risk of developing preeclampsia and the importance of early prenatal care to implement preventive strategies. 5 If preeclampsia develops, they face increased lifetime risks of cardiovascular disease, stroke, diabetes, and chronic kidney disease, requiring lifelong follow-up. 6, 5, 7