What is the most common cause of rhinitis during pregnancy?

The most common cause of rhinitis during pregnancy is often attributed to preexisting allergic rhinitis. Many women who already have allergies may notice an exacerbation of their symptoms during pregnancy due to hormonal changes and increased vascular permeability, which can enhance nasal congestion and other allergic responses. The physiological changes associated with pregnancy, including elevated estrogen and progesterone levels, can lead to increased mucosal edema and sensitivity, which in turn can amplify allergic reactions.

While it is true that physiological changes related to pregnancy also contribute significantly to nasal symptoms, they primarily affect those with preexisting allergic conditions rather than being the most common cause in isolation. Newly developed allergies can occur, but they are less common compared to the exacerbation of existing allergic rhinitis. Respiratory infections may lead to nasal symptoms as well but typically do not represent a chronic issue compared to the reiterated challenges faced by those with preexisting allergic conditions. Hence, preexisting allergic rhinitis stands out as the predominant cause of rhinitis in pregnant individuals.