What can cause thin, watery vaginal discharge and itching that gets worse at night?

Causes to consider include fungal infection, bacterial imbalance, irritant or allergic contact dermatitis (pads, soaps, detergents, scented products), perianal parasitic infestation if itching is worse at night, and less commonly other gynecological conditions. Lack of sexual activity does not exclude these causes; many occur without sexual contact.

• Fungal and bacterial imbalances: discharge characteristics and odor may differ.
• Contact/irritant causes: may be related to external products, pads or detergent changes.
• Parasitic causes: consider if itching is markedly worse at night.
• Recurrent or unusually severe symptoms may need further evaluation.

Symptoms alone do not give a definitive diagnosis; examination and, if needed, laboratory tests are important.

The following low-risk measures can often provide relief and remove irritant causes. They do not replace medical assessment; see a clinician if symptoms do not improve.

• Wash the external genital area gently with warm water only; avoid soaps and douching.
• Stop scented products, wet wipes and recent detergent/softener changes; revert to prior products if possible.
• Wear cotton, breathable underwear and avoid tight or synthetic clothing.
• Change pads frequently and use unscented options when possible.
• Avoid scratching; brief cold compresses can relieve itching.

If there is no clear improvement, or symptoms worsen, seek medical evaluation.

The following signs warrant prompt or emergency evaluation. If you have any of these, seek medical attention without delay.

• Severe lower abdominal or pelvic pain
• Fever or feeling generally unwell
• A large, foul-smelling (fishy) discharge
• Vaginal bleeding or marked burning/increase when urinating
• Rapidly spreading genital redness, swelling or increasing pain

These may indicate an infection or a more serious condition that requires urgent care.

After clinical examination, the clinician may order tests to identify the cause. These tests help distinguish among likely diagnoses and guide further management.

• Vaginal examination to assess external and internal genitalia
• Vaginal pH measurement and microscopic (wet mount) examination
• Culture or molecular testing (NAAT) for causative agents if needed
• Dermatology evaluation when external skin findings are prominent

Which tests are required will be decided by the examining clinician.