What exams and tests should be done for a female patient of childbearing age with suspected pregnancy and potential risk factors such as hypertension (high blood pressure) or diabetes, considering her medical history, including previous pregnancies, miscarriages, or fertility issues?

Initial Evaluation of Suspected Pregnancy

When a patient suspects pregnancy, immediately perform a urine pregnancy test (detecting hCG) and confirm with serum quantitative hCG if needed, followed by comprehensive first-trimester laboratory screening including complete blood count, blood type and antibody screen, hepatitis B surface antigen, HIV, syphilis, rubella immunity, and fasting glucose. 1

Pregnancy Confirmation Testing

Primary Screening Test

• Perform a urine hCG test immediately at the first visit when pregnancy is suspected, as this provides rapid, highly sensitive detection of pregnancy with 95.3% sensitivity and 100% specificity 2, 3
• The test is positive when serum hCG ≥5 mIU/mL, and can detect ectopic pregnancy with 100% sensitivity even at concentrations as low as 191 IU/L 3
• If urine is unavailable, whole blood can be substituted with similar or greater accuracy (95.8% sensitivity) using standard point-of-care hCG kits 2

Confirmatory Testing

• Obtain quantitative serum hCG if the clinical picture is unclear, to establish baseline levels and confirm viability 1
• This is particularly important for women with risk factors for ectopic pregnancy or previous pregnancy complications 4

Comprehensive First-Trimester Laboratory Panel

Essential Blood Work (Perform at First Prenatal Visit)

Hematologic Assessment:

• Complete blood count to screen for anemia 1
• Blood type and Rh status with antibody screen to identify blood incompatibilities 1

Infectious Disease Screening:

• Hepatitis B surface antigen (HBsAg) to prevent mother-to-child transmission 1
• HIV testing 1
• Syphilis serology 1
• Rubella immunity status 1

Metabolic Screening:

• Fasting blood glucose at the first prenatal visit to detect pre-existing diabetes 1
• For women with BMI ≥30 kg/m², history of gestational diabetes, family history of diabetes in first-degree relatives, or high-risk ethnicity (Hispanic, Native American, South/East Asian, African American, Pacific Islander), perform early glucose screening at 12-14 weeks 5
• If early screening is negative in high-risk women, mandatory repeat screening at 24-28 weeks 5

Cervical Screening:

• Pap smear and cervical cultures at the initial visit 1

Urinalysis:

• Dipstick urinalysis at first visit; if proteinuria ≥1+ is detected, follow up with albumin-creatinine ratio 4

Risk-Stratified Additional Testing

For Women with Hypertension or Chronic Medical Conditions

Baseline Laboratory Assessment:

• Serum creatinine and urinary albumin-to-creatinine ratio 1
• Liver enzymes and function tests 1
• Uric acid levels (elevated levels predict worse maternal-fetal outcomes) 1
• Complete blood count 1

Clinical Rationale: These baseline values are essential for detecting superimposed preeclampsia, which complicates up to 25% of pregnancies with chronic hypertension 1

For Women with Pre-existing Diabetes

Additional Testing Required:

• Hemoglobin A1C 1
• Thyroid-stimulating hormone 1
• Serum creatinine and urinary albumin-to-creatinine ratio 1
• Comprehensive eye examination for diabetic retinopathy 1

Clinical Context: Women with diabetes have significantly increased risk for hypertensive disorders of pregnancy and require close monitoring from preconception through delivery 6

For Women with Previous Gestational Diabetes

• Perform glucose testing as early as possible at the first prenatal visit (typically 12-14 weeks) 5
• Use either fasting plasma glucose (≥126 mg/dL indicates overt diabetes) or random glucose ≥200 mg/dL with symptoms 5
• If negative, mandatory retest at 24-28 weeks using standard GDM criteria 5

Blood Pressure Monitoring Protocol

Proper Measurement Technique

• Measure BP with patient relaxed, sitting with legs uncrossed, back supported 4
• Arm should be at the level of the right atrium 4
• Use large cuff if upper arm circumference ≥33 cm 4
• Allow 5 minutes of rest before measurement 4

Screening Frequency

• Measure BP at every prenatal visit throughout pregnancy 4
• If BP ≥140/90 mmHg, confirm with repeated measurements 4
• Consider home BP monitoring or 24-hour ambulatory BP monitoring in women with diabetes, nephropathy, or suspected white coat hypertension, using devices validated specifically for pregnancy 4, 7

Critical Pitfall: White coat hypertension occurs in 12% of women with pre-existing diabetes and 84% of those with newly detected elevated office BP in early pregnancy 7. Home BP monitoring is essential to distinguish this from true hypertension requiring treatment.

Second-Trimester Screening (24-28 Weeks)

Universal Gestational Diabetes Screening

• All women should undergo glucose screening at 24-28 weeks regardless of early screening results 5
• Two-step approach: 50g glucose challenge test; if ≥140 mg/dL, proceed to 100g oral glucose tolerance test 5
• One-step approach: 75g oral glucose tolerance test with fasting, 1-hour, and 2-hour measurements 5

Aneuploidy Screening

• Offer multiple marker screening unless amniocentesis is indicated 1
• Maternal serum alpha-fetoprotein screening at 16-18 weeks for neural tube defects 1

Preeclampsia Risk Assessment and Monitoring

High-Risk Criteria Requiring Enhanced Surveillance

Women with any of the following should receive low-dose aspirin 75-162 mg daily starting at 12 weeks through 36 weeks 4:

• Previous preeclampsia (relative risk 7.19) 8
• Chronic kidney disease 4
• Autoimmune disease 4
• Diabetes (relative risk 3.56) 8
• Chronic hypertension 4
• Multiple gestation (relative risk 2.93) 8
• Age ≥40 years (relative risk 1.68-1.96) 8
• BMI ≥35 kg/m² 4

Ongoing Preeclampsia Surveillance

• After 20 weeks, assess for preeclampsia signs at every visit: BP measurement, urinalysis for proteinuria, symptoms evaluation, fetal well-being 8
• If new hypertension develops (≥140/90 mmHg), obtain: complete blood count, liver enzymes, serum creatinine, uric acid, and quantify proteinuria 8
• Preeclampsia diagnosis requires: BP ≥140/90 mmHg after 20 weeks PLUS either proteinuria (>0.3 g/24h or albumin-creatinine ratio ≥30 mg/mmol) OR maternal organ dysfunction OR uteroplacental dysfunction 8

Common Pitfalls to Avoid

• Failing to repeat glucose screening at 24-28 weeks in high-risk women with negative early screening—insulin resistance increases exponentially in second and third trimesters 5
• Overlooking baseline laboratory tests in women with chronic hypertension or diabetes—these are essential for detecting superimposed complications 1
• Not screening for hepatitis B in first trimester—this is crucial for preventing vertical transmission 1
• Treating white coat hypertension unnecessarily—always confirm elevated office BP with home measurements before initiating antihypertensive therapy 4, 7
• Relying on edema or hyperreflexia for preeclampsia diagnosis—these are nonspecific findings and should not be used diagnostically 8
• Delaying aspirin prophylaxis in high-risk women—must start at 12 weeks for maximum benefit 4