Warning Signs of Preeclampsia
Pregnant women with diabetes and hypertension should be monitored for new-onset hypertension (≥140/90 mmHg) after 20 weeks gestation accompanied by proteinuria (≥300 mg/24h or spot urine protein/creatinine ratio ≥30 mg/mmol), as these define preeclampsia, with your patient's pre-existing conditions increasing her risk 2-4 fold. 1, 2
Core Diagnostic Criteria
The fundamental warning signs that define preeclampsia include:
- New hypertension after 20 weeks gestation: Blood pressure ≥140/90 mmHg on at least two occasions measured 15 minutes apart 1, 3
- New proteinuria: ≥300 mg/24 hours or urine albumin-to-creatinine ratio ≥30 mg/mmol (265 mg/g) in spot urine 1, 3
Severe Features Requiring Immediate Action
Symptoms and signs indicating severe preeclampsia that demand urgent evaluation include: 1
Neurological Warning Signs
- Severe persistent headache unresponsive to usual measures, indicating cerebral edema 1, 4
- Visual disturbances including blurred vision, scotomata, photophobia, or occipital lobe blindness 1
- Hyperreflexia with clonus suggesting impending seizure activity 1
- Convulsions/seizures (eclampsia) requiring immediate delivery 1
Hepatic Involvement
- Right upper quadrant or epigastric pain indicating liver capsule distension from edema and potential hepatic hemorrhage 1
- Nausea and vomiting in the context of elevated blood pressure 1
Severe Hypertension
- Blood pressure ≥160/110 mmHg defines severely elevated blood pressure requiring urgent treatment 1, 3
Fetal Compromise
- Reduced fetal movements or small-for-gestational-age infant suggesting placental insufficiency 1
Laboratory Abnormalities (HELLP Syndrome)
- Hemolysis, Elevated Liver enzymes, Low Platelet count represents a severe variant requiring immediate delivery 1
Critical Context for Your High-Risk Patient
Women with pre-existing diabetes and hypertension face substantially elevated preeclampsia risk—up to 25% compared to 5-7% in the general population. 1, 2
Monitoring Implications
- Your patient requires minimum two-week intervals between assessments from 32 weeks to delivery, with more frequent monitoring if any warning signs develop 1
- Baseline laboratory values (complete blood count, liver enzymes, renal function, uric acid) should be established early to detect superimposed preeclampsia 5
- The International Society of Hypertension recommends measuring serum uric acid as part of hypertension investigation in pregnancy, though it should not be used alone to determine delivery timing 1, 6
Common Pitfalls to Avoid
Pre-existing hypertension can mask the diagnosis of superimposed preeclampsia—look specifically for worsening blood pressure control after 20 weeks and new proteinuria ≥3 g/day, which defines superimposed gestational hypertension with proteinuria. 1
Edema is no longer diagnostic as it occurs in 60% of normal pregnancies and should not be used to diagnose or exclude preeclampsia. 1
Low urinary output in the context of severe hypertension and other symptoms indicates potential renal involvement requiring immediate evaluation. 1
Long-Term Implications
Women with preeclampsia, particularly those with pre-existing diabetes, face 7-fold increased risk of developing diabetic nephropathy and elevated cardiovascular disease risk extending years beyond pregnancy. 7, 8, 9 This underscores the importance of early detection and aggressive management during pregnancy, followed by long-term cardiovascular risk monitoring postpartum. 3, 7