In which trimester is preeclampsia (pregnancy-induced hypertension) most common?

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From the Guidelines

Preeclampsia is most commonly diagnosed in the third trimester of pregnancy, typically after 20 weeks of gestation, with the highest incidence occurring near term (after 37 weeks) 1. The condition is characterized by new-onset hypertension (blood pressure ≥140/90 mmHg) and often proteinuria (protein in the urine) or other signs of organ dysfunction. Some key points to consider include:

  • Preeclampsia affects 3%-8% of pregnancies 1
  • It can develop at any point in the second half of pregnancy, but becomes increasingly common as the pregnancy progresses
  • Risk factors include first pregnancy, history of preeclampsia, chronic hypertension, multiple gestation, obesity, age over 35, and certain medical conditions like diabetes or kidney disease 1
  • Women should be aware of warning signs including severe headaches, visual disturbances, upper abdominal pain, sudden swelling of the face or hands, and decreased urination
  • Regular prenatal visits are essential for early detection, as blood pressure monitoring and urine tests can identify preeclampsia before symptoms appear 1. The exact cause remains unclear, but it involves abnormal placental development and maternal vascular dysfunction. Delivery recommendations vary depending on the severity of preeclampsia, with delivery at 37 weeks recommended for preeclampsia without severe features, and delivery at 34 weeks or as soon as possible after maternal stabilization for preeclampsia with severe features or eclampsia 1.

From the Research

Preeclampsia Trimester Information

  • Preeclampsia is a complication of pregnancy that can occur after 20 weeks of gestation 2.
  • Clinical signs of preeclampsia typically appear in the second half of pregnancy, which includes the third trimester 2.
  • The third trimester is specifically mentioned as a time when preeclampsia often presents, characterized by new-onset hypertension and proteinuria 3, 4.
  • Studies suggest that preeclampsia can progress rapidly to serious complications during the third trimester, making it a critical period for monitoring and management 3, 4.

Trimester-Specific Preeclampsia Details

  • The third trimester is highlighted as a key period for the diagnosis and management of preeclampsia, with severe preeclampsia potentially occurring before 34 weeks of gestation 2, 4.
  • Coagulation parameters, such as fibrinogen, have been found to be significantly different in patients with preeclampsia during the third trimester, suggesting their potential value in suggesting preeclampsia 4.
  • Oral antihypertensive regimens have been studied for the management of severe hypertension in pregnancy, including during the third trimester, with nifedipine, labetalol, and methyldopa being compared for efficacy and safety 5.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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