During pregnancy, hormonal fluctuations and immune system adjustments often lead to nasal symptoms such as congestion and runny nose, which can be highly similar to those of the common cold. Mistaking rhinitis during pregnancy for a common cold can harm the fetus due to inappropriate medication; conversely, neglecting timely intervention for a cold may increase the risk of complications.
Etiology and Mechanism
The core trigger for rhinitis during pregnancy is hormonal changes. Significant increases in progesterone and estrogen lead to vasodilation of the nasal mucosa and increased glandular secretion, causing persistent nasal congestion and runny nose. This physiological change usually begins in the second trimester and is unrelated to allergens. For example, some pregnant women without a history of allergies before pregnancy may still develop typical rhinitis symptoms after exposure to cold air or irritating odors during pregnancy.
The common cold, on the other hand, is primarily caused by viral infections. Pathogens such as rhinoviruses and coronaviruses invade the respiratory tract through droplets, triggering an acute inflammatory response. Its incidence is seasonal, peaking in autumn and winter, and is closely related to contact with infected individuals or contaminated environments.
Symptom Characteristics
Pregnancy rhinitis is primarily characterized by nasal symptoms, including persistent nasal congestion and clear, watery nasal discharge, which worsens in the morning or at night, but without systemic symptoms such as fever, headache, or muscle aches. Some patients may experience a decreased sense of smell, but symptom fluctuations are related to allergen exposure. For example, exposure to dust mites or pollen may temporarily worsen symptoms, but they subside after leaving the environment.
Typical symptoms of the common cold include fever, sore throat, cough, and fatigue, while nasal symptoms are often phased. Initially, clear, watery nasal discharge is predominant, which may turn into purulent discharge after 3-5 days, accompanied by pharyngeal congestion and tonsil enlargement. For example, influenza virus-induced colds are often accompanied by high fever (temperature >38.5℃) and general muscle aches, with symptoms peaking within 3-5 days.
Disease Progression
The course of pregnancy rhinitis is synchronized with hormonal changes during pregnancy, usually lasting throughout the entire pregnancy, with symptoms gradually subsiding after delivery. Some patients may experience nasal structural changes due to prolonged nasal congestion, requiring postpartum treatment with nasal corticosteroids.
The common cold is self-limiting, with most patients experiencing symptom relief within 7-10 days. If complicated by bacterial infection (such as yellow purulent nasal discharge or persistent fever), the course of the illness may extend to two weeks. For example, streptococcal sinusitis requires antibiotic intervention; otherwise, it may develop into chronic inflammation.
Treatment Principles
Treatment of rhinitis during pregnancy focuses on physical relief, avoiding systemic medication. Nasal irrigation with saline solution is recommended 1-2 times daily to clear secretions and reduce mucosal edema. If symptoms are severe, budesonide nasal spray (pregnancy category B) can be used short-term under a doctor's guidance; however, its local bioavailability is low, and systemic absorption is minimal. For example, a clinical study of 200 pregnant patients with rhinitis showed that after saline irrigation combined with nasal corticosteroids, 85% of patients experienced significant improvement in nasal congestion symptoms, with no adverse fetal reactions.
Treatment of the common cold requires medication selection based on symptoms. For fever exceeding 38.5℃, acetaminophen can be taken orally to reduce fever; for severe cough, honey water can be used for relief (use with caution in early pregnancy); for severe runny nose, a short-term course of second-generation antihistamines (such as loratadine) can be used. Compound cold medicines containing pseudoephedrine should be strictly avoided, as they may constrict uterine blood vessels, increasing the risk of fetal hypoxia. For example, the US FDA classifies pseudoephedrine as a pregnancy category C drug, allowing its use only after weighing the risks and benefits.
Risk Assessment
If rhinitis during pregnancy is not addressed promptly, it may lead to chronic nasal congestion and sleep apnea, indirectly affecting fetal oxygen supply. However, overall, the risk is lower than that of a common cold. For example, a follow-up study showed that the incidence of fetal growth restriction in pregnant women with rhinitis was only 3%, significantly lower than in women with a cold.
Common cold viruses may affect fetal development through the placenta, increasing the risk of miscarriage and premature birth. Influenza viruses are particularly dangerous, potentially causing damage to the fetal nervous system.
The differentiation of nasal symptoms during pregnancy requires a combination of medical history, symptom characteristics, and laboratory tests. If symptoms persist for more than two weeks, are accompanied by fever or purulent nasal discharge, or are unresponsive to physical therapy, a nasal endoscopy or allergen testing should be performed promptly. Medication use during pregnancy must strictly adhere to the principle of "minimum effective dose, shortest course of treatment," prioritizing medications classified as pregnancy category B or higher. Through scientific differentiation and standardized management, the health of both mother and baby can be maximized.
