Differential Diagnosis for a 20 Week Pregnant Woman with Shortness of Breath

• Single Most Likely Diagnosis

  • Physiological dyspnea of pregnancy: This condition is common during pregnancy, especially after the 20th week, due to the enlarging uterus pushing against the diaphragm and reducing lung capacity. The increased progesterone levels also lead to increased ventilation.

• Other Likely Diagnoses

  • Anemia: Common in pregnancy due to increased blood volume and demand for iron, leading to reduced oxygen-carrying capacity and shortness of breath.
  • Gestational hypertension or preeclampsia: Can lead to pulmonary edema, causing shortness of breath.
  • Asthma: Pre-existing asthma can worsen during pregnancy, especially if not well-controlled.

• Do Not Miss Diagnoses

  • Pulmonary embolism: Although less common, it is a life-threatening condition that requires immediate attention. Pregnancy increases the risk of thromboembolism due to increased blood clotting factors.
  • Cardiac disease (e.g., peripartum cardiomyopathy): Can present with shortness of breath and is critical to diagnose early for appropriate management.
  • Pneumonia: Infection can be more severe during pregnancy, and prompt diagnosis and treatment are essential.

• Rare Diagnoses

  • Amniotic fluid embolism: A rare but potentially fatal condition where amniotic fluid enters the maternal circulation, causing a severe reaction.
  • Thyroid storm: Although rare, thyroid disorders can occur during pregnancy, and a thyroid storm can present with shortness of breath among other symptoms.
  • Idiopathic pulmonary arterial hypertension: A rare condition that can be exacerbated by pregnancy, leading to severe shortness of breath and other symptoms.