What is the recommended workup for a pregnant patient with a history of preeclampsia?

Preconception Workup for Women with Prior Preeclampsia

Women with a history of preeclampsia preparing for pregnancy require a comprehensive preconception evaluation focused on identifying modifiable risk factors, screening for underlying medical conditions, and establishing baseline organ function to guide future pregnancy management. 1

Preconception Medical Evaluation

Cardiovascular and Metabolic Assessment

• Screen for chronic hypertension with blood pressure measurements, as women with prior preeclampsia have significantly elevated lifetime cardiovascular disease risk 2, 3
• Assess for diabetes mellitus (both type 1 and type 2), as pre-existing diabetes substantially increases recurrent preeclampsia risk 4, 1
• Evaluate lipid profile and cardiovascular risk factors, recognizing that prior preeclampsia is an independent risk factor for future cardiovascular disease 3, 5

Renal Function Assessment

• Obtain baseline serum creatinine and urinalysis to identify underlying renal disease, as persistent proteinuria or renal dysfunction requires further workup 2, 1
• Screen for chronic kidney disease, which is both a risk factor for recurrent preeclampsia and a long-term sequela of the condition 3, 5

Laboratory Baseline Studies

• Obtain complete blood count (hemoglobin, platelets) to establish baseline hematologic function 2, 1
• Measure liver transaminases to assess hepatic function before pregnancy 2, 1
• Consider thrombophilia screening in select cases, particularly if early-onset or severe preeclampsia occurred, though routine screening remains controversial 3

Risk Stratification and Counseling

Assess Recurrence Risk Factors

• Evaluate gestational age at prior preeclampsia onset, as early-onset disease (<34 weeks) carries substantially higher recurrence risk (up to 65%) compared to term disease 1, 6
• Document severity of prior disease, including presence of HELLP syndrome, eclampsia, or end-organ dysfunction 1, 6
• Identify additional risk factors including maternal age >40 years, BMI >35 kg/m², multiple gestation plans, and pregnancy interval >10 years 4

Provide Specific Recurrence Counseling

• Inform patients that overall recurrence rate is approximately 13.8-20.7%, with milder disease typically occurring upon recurrence 6
• Counsel about increased risks of preterm delivery, fetal growth restriction, placental abruption, and fetal death in subsequent pregnancies 1, 5

Prevention Strategy Planning

Low-Dose Aspirin Prophylaxis

• Prescribe aspirin 100-162 mg daily starting at 12 weeks gestation (ideally before 16 weeks) and continuing until 36-37 weeks, as this reduces preterm preeclampsia risk by approximately 62% 4, 7
• Counsel that aspirin should be initiated early in pregnancy for maximum benefit, emphasizing the importance of early prenatal care 4, 5

Calcium Supplementation Assessment

• Evaluate dietary calcium intake and recommend supplementation of 1.5-2 g daily if intake is <600-800 mg/day, which reduces preeclampsia risk by 36-64% 4

Lifestyle Optimization

• Recommend weight optimization if BMI >35 kg/m², as obesity is a modifiable risk factor 4, 7
• Encourage regular exercise (50 minutes of aerobic, strength, and flexibility training 3 times weekly) 4
• Advise normal salt intake without restriction, as excessive restriction may induce low intravascular volume 4
• Counsel against vitamin C and E supplementation, as these may worsen outcomes 4

Establish Early Pregnancy Surveillance Plan

First Trimester Planning

• Schedule early prenatal care with first-trimester ultrasound for accurate dating and fetal number confirmation 1
• Plan for more frequent prenatal visits than standard care, given increased risk of complications 1
• Arrange baseline laboratory studies in early pregnancy to compare against preconception values 1

Monitoring Strategy

• Establish plan for home blood pressure monitoring or more frequent nursing contacts throughout pregnancy 1
• Schedule serial ultrasound evaluations for fetal growth and amniotic fluid assessment, particularly if prior pregnancy involved fetal growth restriction 1

Address Underlying Medical Conditions

Optimize Chronic Conditions

• Achieve optimal blood pressure control before conception if chronic hypertension is present 1, 3
• Optimize glycemic control if diabetes is diagnosed 1
• Treat any identified renal disease and establish nephrology co-management if indicated 2, 3

Medication Review

• Review and adjust antihypertensive medications to pregnancy-safe options (labetalol, nifedipine, methyldopa) before conception 2

Common Pitfalls to Avoid

• Do not delay preconception evaluation, as identifying and treating underlying conditions before pregnancy significantly improves outcomes 1, 3
• Do not minimize the importance of early aspirin initiation, as starting after 16 weeks substantially reduces efficacy 4, 5
• Do not assume recurrence will be equally severe, as most recurrent cases are milder, but vigilance remains essential 6
• Do not neglect long-term cardiovascular risk counseling, as this represents a critical opportunity for lifelong health optimization 3, 5