Preeclampsia

Preeclampsia causes pregnancy-related hypertension. It is defined as systolic blood pressure of 140 mm Hg or more or diastolic blood pressure of 90 mm Hg or more on two occasions at least 4 hours apart, or shorter interval timing of 160 mm Hg or more or diastolic blood pressure of 110 mm Hg or more after 20 weeks of gestation.

Last Updated: February 26, 2024

Preeclampsia causes 2-8% of pregnancy-related problems globally. In low-income nations, it generates 9-26% of maternal deaths, and in high-income countries, 16%.

Preeclampsia has many risk factors, including the following:

  • Nulliparity, 
  • multi-gestation pregnancy, 
  • advanced maternal age greater than 35.

Nobody knows for sure the exact cause of preeclampsia. Experts think that the placenta (the organ that develops in the uterus during pregnancy and is responsible for providing oxygen and nutrients to the fetus) plays a role in its development. In preeclampsia, the placenta may not get as much blood as it needs, which can be bad for the mother and the baby.

Many people with preeclampsia don't feel sick at all. For those who do, high blood pressure, protein in the urine, and edema are some of the first signs of preeclampsia (this can cause weight gain and swelling).

There are also other signs of preeclampsia:

  • Headaches
  • Blurry vision sensitivity to light
  • Dark spots in the vision
  • Right-sided abdominal pain
  • Hands and face swell up (edema)
  • Shortness of breath

Many pregnant mothers don't know they have preeclampsia until they go to a prenatal appointment and have their blood pressure and urine checked.

Signs of severe preeclampsia may include:

  • Hypertensive emergency where blood pressure is 160/110 mmHg or higher
  • Poor kidney or liver function
  • Fluid in the lungs
  • Low blood platelet levels (thrombocytopenia).
  • Poor urine output

Pregnancy-induced hypertension diagnosis includes:

  • Urinalysis to evaluate and below are the ways to check;
  • Urine dipstick result of 2+ or greater 
  • 24-hour urine collection sample significant for 300mg or greater 
  • Urine protein to creatinine ratio significant for 0.3 or greater
  • Complete blood count for thrombocytopenia (less than 100 K/mm platelets);
  • Metabolic panel to test liver function (with liver enzymes greater than two times the upper limit of normal);
  • Renal insufficiency (serum concentration 1.1 mg/dL or higher, or twice baseline).

All abnormal test findings must exclude prior abnormalities or secondary causes for the findings to be diagnostic of preeclampsia.

In many circumstances, preeclampsia can be diagnosed without high blood pressure and proteinuria. In the absence of proteinuria and new-onset hypertension, other new-onset symptoms such as thrombocytopenia, renal insufficiency, pulmonary edema, poor liver function, or new-onset headache may be used for diagnosis. This is preeclampsia without severe characteristics, including new-onset severe range blood pressures (160 mmHg or higher, 110 mmHg or higher on two readings at least 4 hours apart).

Treatment

Early identification and identification are crucial to managing preeclampsia. Labetalol or nifedipine can be used to control blood pressure.

Delivering the fetus is the final and most effective treatment for preeclampsia. There are risks associated with the expectant approach. However, continuous observation is an option for preterm pregnancies in individuals with well-controlled gestational hypertension or preeclampsia without severe symptoms and appropriate antepartum (before giving birth) tests.

Women at risk for preeclampsia can take some steps before and during pregnancy to lower their chances of getting it. This includes:

  • Lose weight if overweight or obese prior to pregnancy;
  • Blood pressure and sugar control before pregnancy;
  • Maintain an exercise routine;
  • Have a good amount of sleep every night;
  • Eating low-salt and caffeine-free foods.

Taking one baby aspirin daily has been shown to reduce the risk of preeclampsia by about 15%. Women at risk for preeclampsia should take aspirin as early in their pregnancies as possible (at around 12 weeks of gestation).

References

Karrar SA, Hong PL. Preeclampsia. [Updated 2022 Jun 9]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK570611/

Cleveland Clinic (2022). Preeclampsia. Retrieved November 2, 2022, from https://my.clevelandclinic.org/health/diseases/17952-preeclampsia#symptoms-and-causes

Last Updated: February 26, 2024