What causes dizziness in a pregnant patient?

From the Guidelines

Dizziness in pregnant patients is most commonly caused by iron deficiency anemia, which can lead to reduced oxygen delivery to the brain and other tissues, resulting in symptoms such as fatigue, weakness, and dizziness. According to a recent study published in 2021 1, iron deficiency anemia is a major global health problem, affecting more than 1.2 billion people worldwide, including pregnant women. The study highlights that symptoms of iron deficiency anemia include fatigue, reduced exercise capacity, cardiac palpitations, and dizziness.

Causes of Dizziness in Pregnancy

Other factors that can contribute to dizziness in pregnancy include:

• Hormonal changes, particularly increased progesterone, which can relax blood vessels and lead to lower blood pressure and reduced blood flow to the brain
• Physical changes, such as the growing uterus, which can compress major blood vessels and reduce blood return to the heart
• Low blood sugar (hypoglycemia) from changing eating patterns or increased metabolic demands
• Dehydration, as pregnant women need more fluids
• Inner ear disturbances, hyperventilation from anxiety, and certain medications

Management of Dizziness in Pregnancy

Management of dizziness in pregnancy typically includes:

• Rising slowly from sitting or lying positions
• Staying hydrated
• Eating regular small meals
• Avoiding prolonged standing
• Lying on the left side to improve circulation While usually benign, persistent or severe dizziness should be reported to a healthcare provider to rule out more serious conditions like preeclampsia. A study published in 2011 1 highlights the importance of understanding the hemodynamic changes that occur during pregnancy, which can also contribute to dizziness. However, the most recent and highest quality study 1 suggests that iron deficiency anemia is a significant contributor to dizziness in pregnant patients.

From the Research

Causes of Dizziness in Pregnant Patients

• Hormonal changes and modifications in vascular dynamics are typical causes of vertigo during pregnancy 2
• Physiologic changes during pregnancy, including changes in blood volume, heart rate, stroke volume, cardiac output, vascular resistance, and colloid osmotic pressure, can also contribute to dizziness 3
• Other potential causes of dizziness in pregnant patients include:
  • Benign paroxysmal positional vertigo
  • Meniere disease
  • Vestibular neuritis
  • Orthostatic hypotension, which can be diagnosed based on an orthostatic challenge and implies a persistent systolic/diastolic blood pressure decrease of at least 20/10 mm Hg upon standing 4, 5, 6

Pathophysiology and Treatment

• The pathophysiology of vertigo during pregnancy involves vestibular and central nervous system adaptations 2
• Treatment options for vertigo during pregnancy include dietary changes, vestibular therapy, medicines, and surgical procedures 2
• Orthostatic hypotension can be treated by addressing the underlying cause, and management strategies may include increasing fluid and salt intake, wearing compression stockings, and avoiding sudden changes in position 6

Assessment and Evaluation

• Evaluation of dizziness in pregnant patients focuses on determining whether the etiology is peripheral or central 4
• The HINTS (head-impulse, nystagmus, test of skew) examination can help distinguish peripheral from central etiologies 4
• Orthostatic blood pressure measurement, a full cardiac and neurologic examination, assessment for nystagmus, and the Dix-Hallpike maneuver are also important components of the physical examination 4