What is a cause of pregnancy-related dyspnea?

• A. Dehydration
• B. Increased estrogen causing vascular congestion leading to nasal stuffiness rhinitis and epistaxis
• C. Increase in progesterone causing diaphragm weakness
• D. Anemia

Answer: (B)

During pregnancy, rising estrogen levels cause increased vascularity and edema of mucous membranes, including the nasal passages. This leads to nasal congestion, rhinitis, and even epistaxis. That nasal mucosal swelling can contribute to a sense of breathing difficulty for some patients, especially as the uterus grows and breathing becomes more effortful, making mouth breathing feel more noticeable. So the nasal congestion driven by estrogen-related vascular changes is a common, pregnancy-specific factor that can manifest as dyspnea.

Other options don’t fit as well with pregnancy-related dyspnea. Dehydration isn’t a typical driver of dyspnea in pregnancy. Anemia can cause dyspnea, but the question highlights a mechanism linked to hormonal vascular changes affecting the nasal passages, which is more directly connected to the symptom pattern described. An increased progesterone effect does not weaken the diaphragm; in fact it tends to increase respiratory drive rather than cause diaphragmatic weakness.