Preeclampsia is one of those words you may hear in the OPD and then forget—until a blood pressure reading climbs, your hands swell, or a headache appears that feels unlike any other. Questions can come fast: Is it serious? Is baby okay? Should you go in now?
The reassuring part is that early detection changes outcomes. Regular BP checks, urine testing, blood work when needed, and monitoring the baby help clinicians identify preeclampsia, decide whether there are severe features, and manage it with a clear, step-by-step plan.
What preeclampsia is (and why it matters)
Preeclampsia is a pregnancy complication most often starting after 20 weeks, defined by new-onset hypertension plus signs that organs are under strain. It is not only a “BP issue”, it is a placenta-driven, whole-body condition that can worsen quickly.
Clinicians diagnose preeclampsia when blood pressure is elevated (often ≥140/90 mmHg, confirmed on repeat readings) and there is either:
- proteinuria (protein leaking into urine), or
- evidence of organ involvement (for example low platelets, rising creatinine, elevated liver enzymes, pulmonary edema, or neurologic/visual symptoms).
Why it matters: it can affect the parent’s kidneys, liver, brain, lungs, and clotting system, and it can affect the baby through placental blood flow (growth restriction, distress, prematurity).
When preeclampsia can happen (including after delivery)
Preeclampsia usually appears after 20 weeks, often in the third trimester. It can also begin during labour.
Two timing patterns are commonly discussed:
- Early-onset preeclampsia: before 34 weeks (more placental dysfunction, higher chance of fetal growth restriction)
- Late-onset preeclampsia: 34 weeks or later (baby is more mature, but rapid worsening is still possible)
Important: postpartum preeclampsia can develop after delivery—often in the first days, sometimes up to about 6 weeks postpartum. New symptoms after birth should not be brushed off.
Preeclampsia vs gestational hypertension vs chronic hypertension
These terms sound similar but the management can differ:
- Gestational hypertension: new high BP after 20 weeks, without proteinuria and without organ dysfunction at diagnosis.
- Preeclampsia: new high BP after 20 weeks with proteinuria and/or organ dysfunction.
- Chronic hypertension: high BP known before pregnancy, detected before 20 weeks, or persisting after delivery.
If someone already has chronic hypertension and develops new findings (new/worsening protein in urine, platelets dropping, creatinine rising, elevated liver enzymes, headache/vision symptoms, pulmonary edema), clinicians suspect superimposed preeclampsia.
Preeclampsia with severe features
“Severe features” is a medical label that signals higher short-term risk, not something you caused.
Severe features include:
- BP in the severe range: ≥160/110 mmHg (confirmed)
- Platelets <100,000/µL
- Creatinine ≥1.1 mg/dL or doubling from baseline
- Liver involvement: markedly elevated AST/ALT and/or strong right upper abdominal/epigastric pain
- Pulmonary edema
- New neurologic/visual symptoms (severe headache, blurred vision, seeing spots)
When severe features are present, hospital care is usually needed, along with seizure prevention (often magnesium sulfate) and delivery planning once stabilised.
Why preeclampsia happens in the body (simple explanation)
Preeclampsia begins with the placenta. Early in pregnancy, blood vessels should remodel so blood flows easily to the placenta. When this remodeling is incomplete, the placenta can become relatively under-perfused and stressed.
A stressed placenta releases signals that affect the endothelium (the lining of blood vessels). Blood vessels constrict (BP rises), become leakier (swelling and fluid shifts), and clotting regulation can change. Because blood vessels are everywhere, the kidneys, liver, brain, lungs, and blood system can all show signs of strain.
In some centres, angiogenic biomarkers (like the sFlt-1/PlGF ratio) may be used as an additional tool when the diagnosis is uncertain, they support, but do not replace, standard BP, urine, blood tests, and fetal assessment.
Symptoms and warning signs of preeclampsia
Preeclampsia can be silent—this is why BP and urine checks at every visit matter.
Call or go in for assessment if you have:
- Severe or persistent headache, especially if not improving
- Vision changes (blurred vision, spots, flashing lights, light sensitivity)
- Right upper abdominal/epigastric pain (under the ribs, not “usual acidity”)
- New/worsening shortness of breath, chest tightness, trouble lying flat
- Markedly reduced urination
- Sudden swelling of face/hands, or very rapid swelling/weight gain
- Clearly reduced fetal movements
Home BP readings that need action:
- Repeated ≥140/90: contact your doctor/maternity unit promptly.
- Any ≥160/110: urgent evaluation is safest.
If you feel you might faint, or you have a seizure, call emergency services.
How preeclampsia is diagnosed
Diagnosis is based on BP plus urine/blood findings.
Blood pressure
- Hypertension: ≥140/90 on two readings at least 4 hours apart after 20 weeks.
- Severe range: ≥160/110.
Accurate technique matters: correct cuff size, seated rest, arm supported at heart level.
Urine testing
- Dipstick can screen but is less reliable.
- Spot urine protein/creatinine ratio ≥0.3 supports significant proteinuria.
- 24-hour urine ≥300 mg confirms proteinuria.
Blood tests
Common tests include:
- platelets
- creatinine (sometimes urea)
- AST/ALT (liver enzymes)
- sometimes LDH/coagulation tests depending on severity and HELLP concern
Baby monitoring
Because preeclampsia can reduce placental function, clinicians may recommend:
- serial growth ultrasound and amniotic fluid assessment
- Doppler studies (often umbilical artery)
- NST/BPP depending on gestational age and risk
Who is at higher risk
Preeclampsia is more likely with:
- first pregnancy
- prior preeclampsia
- family history
- chronic hypertension
- diabetes
- kidney disease
- overweight/obesity
- lupus or antiphospholipid syndrome
- twins/triplets
- maternal age over 35
- assisted reproduction (including IVF)
Prevention (what is actually used)
Prevention is individualised. Common medical strategies include:
- Low-dose aspirin for higher-risk pregnancies (often started between 12–28 weeks, ideally before 16 weeks, only under clinician advice)
- Calcium supplementation when dietary calcium intake is low (dose as advised)
Strict bed rest and routine salt restriction are not proven ways to prevent preeclampsia.
Treatment and management
The only definitive treatment for preeclampsia is delivery of the baby and placenta. Until then, care focuses on keeping parent and baby stable.
Depending on severity and gestational age, management may include:
- frequent BP checks (clinic and sometimes home logs)
- repeat urine and blood tests to track trends
- fetal surveillance (ultrasound, Dopplers, NST/BPP)
- antihypertensives (commonly labetalol, nifedipine, hydralazine) to reduce stroke risk when BP is high
- magnesium sulfate for seizure prevention in severe disease
- antenatal corticosteroids if preterm delivery is likely (often before 34 weeks)
- careful fluid management to reduce risk of pulmonary edema
Delivery planning
Typical patterns (individual plans can differ):
- Without severe features: delivery often planned around 37 weeks.
- With severe features: delivery often recommended at or after 34 weeks, or earlier if parent/baby becomes unstable.
- Before 34 weeks: in selected stable cases, hospital monitoring may aim to gain time for fetal maturity, delivery is advised if risk increases.
Vaginal birth is often possible with induction if conditions are favourable, caesarean may be recommended if rapid delivery is needed or fetal status is concerning.
Postpartum preeclampsia: do not ignore symptoms
Postpartum preeclampsia can appear after birth (up to about 6 weeks). Seek prompt assessment for:
- severe headache
- vision changes
- upper abdominal pain
- breathlessness or chest symptoms
- sudden swelling
- high BP readings at home
Many care plans include BP checks soon after discharge and again in the following weeks.
Long-term health after preeclampsia
A history of preeclampsia is linked to higher long-term risk of chronic hypertension, heart disease and stroke, and sometimes kidney disease—especially after early-onset or severe disease.
This is why it helps to tell your family physician in future: “I had preeclampsia.” It changes long-term screening priorities.
Key takeaways
- Preeclampsia is high BP after 20 weeks with protein in urine and/or organ involvement.
- It can be silent, routine BP and urine checks are essential.
- Urgent symptoms include severe headache, vision changes, right upper abdominal pain, breathlessness, very low urine output, and BP ≥160/110.
- Tests include urine protein testing, blood tests (platelets, creatinine, AST/ALT), and baby monitoring (ultrasound, Doppler, NST/BPP).
- Management aims to stabilise, delivery is definitive treatment.
- Postpartum preeclampsia can occur up to about 6 weeks after delivery.
- For personalised guidance and free child health questionnaires, you can download the Heloa app.
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