It hurts when the vaginal opening gets wet.

　　Pain upon moisture at the vaginal opening may be caused by local skin sensitivity, improper vulvar hygiene, sexual activity, vulvitis, or vaginitis, and can be improved according to the specific cause. It is recommended to seek timely medical evaluation and treatment under the guidance of a healthcare provider.

　　1. Local Skin Sensitivity

　　The skin around the vaginal opening is naturally sensitive. Using unsuitable sanitary products may irritate the local skin, making pain more likely in moist conditions. Choose high-quality, soft, breathable sanitary pads and underwear—such as cotton underwear—and avoid products containing fragrances, fluorescent agents, or other potential irritants.

　　2. Improper Vulvar Hygiene

　　Failure to clean the area promptly can lead to accumulation of secretions, which may foster bacterial growth in damp environments and cause discomfort. Wash the vulva with warm water 1–2 times daily to maintain cleanliness, but avoid using harsh cleansers or douching excessively, as this may disrupt the natural balance.

　　3. Sexual Activity

　　Insufficient lubrication, rough movements, or excessive frequency during intercourse may damage the mucous membrane of the vaginal opening, leading to pain when exposed to moist environments such as bodily secretions. Ensure adequate foreplay to promote natural vaginal lubrication, and use water-based lubricants if needed. Perform sexual activity gently and avoid excessive force, while also moderating frequency.

　　4. Vulvitis

　　Inflammation of the vulvar skin or mucosa—caused by infection with pathogens such as bacteria or fungi, or irritation from urine, feces, or vaginal secretions—can result in symptoms including redness, swelling, itching, and pain. Moisture at the vaginal opening may worsen the pain. Under medical guidance, topical medications such as erythromycin ointment, clotrimazole cream, or compound Phellodendron liquid dressing may be used to relieve symptoms.

　　5. Vaginitis

　　An imbalance in the normal vaginal flora allows pathogens to multiply and trigger inflammation. Common types include bacterial vaginosis and fungal (yeast) vaginitis, which increase vaginal discharge that may irritate the vaginal opening and cause pain—particularly when moisture exacerbates discomfort. Under a doctor's supervision, treatments such as metronidazole suppositories, nystatin tablets, or Baofukang suppositories may be prescribed.

　　In daily life, maintain regular vulvar hygiene, avoid using irritating cleansers, and refrain from over-cleaning the vagina to prevent disruption of its natural microbial balance. Use fragrance-free, alcohol-free personal care products suitable for your skin type.