What is the management and treatment of hyperplacentosis during pregnancy?

Management of Hyperplacentosis During Pregnancy

Hyperplacentosis requires close maternal and fetal surveillance with management focused on its associated complications—particularly preeclampsia, pruritus, and fetal growth restriction—rather than the placental hyperactivity itself.

Understanding Hyperplacentosis

Hyperplacentosis represents a syndrome of increased placental metabolic activity manifesting as elevated human chorionic gonadotropin levels, theca luteal cysts, preeclampsia, and/or pruritus, typically diagnosed in the third trimester 1. The condition is associated with placental vascular malformations and carries significant risk for both maternal and fetal complications 1.

Primary Surveillance Strategy

Maternal Monitoring

• Blood pressure assessment: Monitor for development of gestational hypertension or preeclampsia, as these are common manifestations of hyperplacentosis 1. Check BP at every visit, with urgent treatment required if BP reaches ≥160/110 mmHg 2.

• Laboratory surveillance at least twice weekly in the second half of pregnancy 3:

  • Urine protein/creatinine ratio (abnormal if ≥30 mg/mmol) to detect proteinuria 3
  • Hemoglobin and platelet counts, as decreasing values indicate progression to preeclampsia 3
  • Liver transaminases, creatinine, and uric acid levels 3

• Clinical assessment for preeclampsia symptoms 3:

  • Severe headache or visual disturbances
  • Epigastric pain
  • Neurological signs including clonus 3

Fetal Monitoring

• Ultrasound assessment at diagnosis and every 2 weeks if initial evaluation is normal 2:

  • Fetal biometry to detect growth restriction, which can occur with severe placental thrombosis in hyperplacentosis 4
  • Amniotic fluid volume
  • Umbilical artery Doppler studies 2

• More frequent monitoring if fetal growth restriction is detected, as this indicates severe placental dysfunction 4.

Management of Associated Complications

If Preeclampsia Develops

• Hospital assessment is mandatory when preeclampsia is first diagnosed 2.

• Antihypertensive therapy for BP consistently ≥140/90 mmHg, targeting diastolic BP of 85 mmHg (systolic <160 mmHg) 2:

  • First-line agents: oral methyldopa, labetalol, or nifedipine 2
  • Avoid ACE inhibitors, ARBs, and direct renin inhibitors due to severe fetotoxicity 2, 5

• Urgent treatment for severe hypertension (≥160/110 mmHg) with IV labetalol, oral nifedipine, or IV hydralazine in a monitored setting 2, 5.

• Magnesium sulfate for seizure prophylaxis in women with proteinuria and severe hypertension or neurological symptoms 2.

• Do NOT use plasma volume expansion routinely 2.

If Severe Hypertension Occurs

• Immediate hospitalization and treatment targeting BP reduction to 140-150/90-100 mmHg within 15-60 minutes 5.

• IV labetalol as first-line agent with bolus administration repeated until BP controlled 5.

• Monitor for maternal early warning criteria including altered mental status, oliguria, oxygen saturation <95%, and non-remitting headache 5.

Management of Pruritus

While pruritus is a recognized manifestation of hyperplacentosis 1, the evidence does not provide specific treatment protocols. Standard obstetric evaluation to exclude other causes of pruritus (particularly intrahepatic cholestasis of pregnancy) is warranted through liver function testing, which is already part of the recommended surveillance 3.

Timing of Delivery

• Delivery at 37-38 weeks for gestational hypertension or mild preeclampsia without other complications 2, 5.

• Immediate delivery indicated for 5:

  • Severe heart failure
  • Fetal distress
  • Uncontrolled severe hypertension despite treatment
  • Eclampsia

• Delivery is the definitive treatment for severe preeclampsia 5.

Critical Pitfalls to Avoid

• Do not delay treatment of severe hypertension 5.
• Do not combine nifedipine with magnesium sulfate due to risk of severe hypotension 5.
• Do not restrict salt intake, as this may induce low intravascular volume near delivery 2.
• Do not reduce antihypertensives if diastolic BP falls <80 mmHg, as this may impair uteroplacental perfusion 2, 3.

Postpartum Considerations

• Monitor BP for 72 hours in hospital and 7-10 days postpartum 3.
• Hypertension should resolve within 6-12 weeks postpartum; persistence suggests pre-existing hypertension 5.
• Annual cardiovascular risk assessment lifelong is recommended 3.