Does rhinitis during pregnancy harm the fetus

Pregnancy is a unique stage in a woman's life, during which various bodily systems undergo a series of adaptive changes. However, when rhinitis, a common respiratory illness, coincides with pregnancy, many expectant mothers worry: Will symptoms like nasal congestion and runny nose affect the health of the unborn child? In reality, rhinitis during pregnancy itself does not typically pose a direct threat to the fetus. However, if symptoms persist or are improperly treated, they may indirectly affect fetal development through maternal hypoxia, medication risks, and the spread of infection.

Maternal Hypoxia

Rhinitis during pregnancy is primarily characterized by nasal congestion and clear runny nose, often triggered by hormonal changes (such as elevated estrogen and progesterone levels, which lead to dilation of nasal mucosal blood vessels) or allergens. Physiological nasal congestion does not typically lead to severe hypoxia, as the fetus can normally receive oxygen through the placenta. However, if chronic nasal congestion forces pregnant women to breathe through their mouths, it may cause the following problems:

Nighttime sleep apnea: Severe nasal congestion can cause a decrease in a pregnant woman's blood oxygen saturation during sleep. While healthy pregnant women may have compensatory mechanisms to mitigate short-term effects, chronic hypoxia may interfere with fetal brain oxygen supply and increase the risk of intrauterine growth retardation.

The cumulative effects of chronic hypoxia: Studies have shown that for every 1% decrease in maternal blood oxygen saturation, fetal umbilical artery resistance may increase, leading to reduced nutrient delivery efficiency. During ultrasound monitoring, slow growth of the fetal biparietal diameter or shorter-than-normal femoral length may be early signs of hypoxia.

Suggestions: Pregnant women can improve ventilation by sleeping on their side, use a humidifier to maintain room humidity (40%-60%), and use a physiological seawater nasal spray three to four times daily. Avoid irritation from cold air and dust.

Medication Risks

During pregnancy, medications must strictly adhere to the principle of "minimum effective dose, shortest treatment course." Some rhinitis medications may cross the placenta and affect the fetus:

Decongestants: Medications containing pseudoephedrine may constrict uterine blood vessels and induce uterine contractions, and their use in early pregnancy is potentially teratogenic.

Antihistamines: First-generation drugs (such as chlorpheniramine) may cross the blood-brain barrier and cause fetal drowsiness. Second-generation drugs (such as loratadine and cetirizine) are relatively safe during pregnancy but should be used under a doctor's supervision.

Glucocorticoids: Category B pregnancy-safe drugs such as nasal budesonide and fluticasone propionate have low systemic absorption and can provide short-term control of moderate to severe allergic rhinitis, but long-term, high-dose use should be avoided.

Spread of Infection

Combined rhinitis with bacterial sinusitis may pose the following risks:

Systemic inflammatory response: Symptoms such as yellow-green purulent rhinorrhea, headache, and fever indicate spread of infection. Pathogens may affect fetal metabolism through the bloodstream, increasing the risk of premature birth or low birth weight. Neonatal Respiratory Distress Syndrome: Severe infection may lead to insufficient surfactant synthesis in the fetal lungs, placing premature infants at increased risk of this complication.

Preventative Measures: If symptoms such as purulent discharge and persistent fever occur, immediate consultation with an ENT and obstetrician is indicated, with penicillins or cephalosporins (pregnancy category B) preferred.

Genetic Predisposition to Allergies

Allergic rhinitis is hereditary. Pregnant women with allergies may increase the risk of their fetus developing allergic conditions such as asthma and eczema after birth. Studies show that if one parent has a history of allergies, the risk of their children developing allergies is 30%-50%; if both parents have a history of allergies, the risk increases to 60%-80%.

Intervention Strategies:

Allergen Avoidance During Pregnancy: Regularly change bed linens and pillowcases, use dust mite-proof covers, and avoid contact with pollen and animal dander.

Probiotic Supplementation: Moderate intake of probiotics such as lactobacilli and bifidobacteria during pregnancy may modulate the fetal immune system and reduce the risk of allergies. Early postpartum intervention: Avoid exposure to irritants such as tobacco smoke and chemical cleaning agents for the first six months. Breastfeeding can strengthen the intestinal barrier function.

Scientific Response

Treatment of rhinitis during pregnancy requires a balanced approach to symptom relief and fetal protection, with non-drug interventions being the preferred approach:

Physical therapy: Nasal irrigation with normal saline solution can clear secretions and allergens once or twice daily; applying a warm towel to the bridge of the nose (around 40°C for 5-8 minutes each) can promote vasodilation.

Environmental control: Maintain indoor humidity at 50%-60%, ventilate regularly, and wash bedding at high temperatures weekly for those allergic to dust mites.

Nutritional support: Appropriate supplementation with vitamin C (such as citrus fruits, but in limited amounts to prevent acid reflux) and zinc (such as nuts and lean meats) can help enhance mucosal immunity.

Regular monitoring: Report rhinitis control to the doctor during prenatal checkups, and perform fetal heart monitoring to assess fetal status if necessary.

Although rhinitis during pregnancy may pose indirect risks, with standardized treatment and daily management, the vast majority of fetuses can develop healthily. Expectant mothers do not need to be overly anxious, but they should be alert to signs of worsening symptoms (such as persistent fever, purulent discharge, and difficulty breathing). They should seek medical attention promptly and strictly follow their doctor's instructions for medication. Remember, maternal health is the best protection for the fetus, and only scientific responses can safeguard the safety of both mother and child.