Bacterial Vaginosis (BV) : Symptoms, Fishy Odour & Treatment

Bacterial Vaginosis (BV) in Hong Kong: A Comprehensive Guide to Symptoms, Treatment, and Prevention

Bacterial Vaginosis is the most common vaginal condition in women of reproductive age worldwide, including Hong Kong, yet it remains widely misunderstood. Unlike a yeast infection, BV is not caused by a fungus but by a significant imbalance in the vagina's natural bacterial ecosystem. This guide provides a thorough, medically accurate introduction to BV, tailored to address the specific questions and concerns of women in Hong Kong.

What is Bacterial Vaginosis (BV)?

Bacterial Vaginosis is a clinical condition caused by an overgrowth of certain bacteria in the vagina, which upsets the natural balance. A healthy vagina maintains a delicate equilibrium, predominantly populated by beneficial Lactobacillus bacteria. These "good" bacteria produce lactic acid, keeping the vaginal environment slightly acidic and preventing the overgrowth of other organisms. In BV, the number of Lactobacilli decreases, allowing an overgrowth of other types of bacteria (such as Gardnerella vaginalis, Prevotella, Mobilincus spp., Megaspahera spp., Sneathea spp. and others). This shift leads to the characteristic symptoms and changes in vaginal discharge.

Signs and Symptoms: How to Recognize BV

The most common symptom of BV is a change in vaginal discharge. Key characteristics include:

Thin, watery, and greyish-white discharge.
A strong, unpleasant "fishy" odour, which is often more noticeable after sexual intercourse or during menstruation.
Itching or burning in the vaginal area is not a primary symptom of BV. If you experience significant itching or burning, it may indicate a different condition, such as a yeast infection.

Crucially, up to 50% of women with BV may have no symptoms at all¹. However, even asymptomatic BV can lead to health complications.

Differentiating BV from Other Common Infections

It's easy to confuse BV with other vaginal issues like yeast infections. The table below helps clarify the key differences:

Feature	Bacterial Vaginosis (BV)	Vaginal Yeast Infection (Candidiasis)	Trichomoniasis (STI)
Primary Cause	Bacterial imbalance (not an STI)	Overgrowth of Candida fungus	Parasite (Trichomonas vaginalis)
Discharge	Thin, greyish-white, homogenous	Thick, white, clumpy (like cottage cheese)	Frothy, yellow-green, often copious
Odour	Strong fishy smell	Usually odourless or yeast-like	Strong, unpleasant smell
Itching/Burning	Uncommon (mild if present)	Very common, often severe	Common, can be significant
Vaginal pH	Elevated (usually above 4.5)	Normal (usually below 4.5)	Elevated (usually above 4.5)

What Causes BV? Risk Factors in the Hong Kong Context

The exact cause of the bacterial imbalance is not fully understood, but certain activities and factors can disrupt the vaginal flora and increase risk:

Sexual Activity: BV is more common in sexually active women. Having a new sexual partner or multiple partners can increase risk. While not classified as a classic STI, it is linked to sexual behaviour.
Douching: This practice disrupts the natural vaginal flora and is a major risk factor. Healthcare professionals strongly advise against douching.
Lifestyle Factors: Smoking has been linked to a higher incidence of BV. Hong Kong's humid climate may also play an indirect role, as wearing tight, non-breathable synthetic clothing for prolonged periods can create a favourable environment for bacterial overgrowth.

Diagnosis: How BV is Confirmed in Hong Kong

If you suspect you have BV, it's important to see a healthcare provider for an accurate diagnosis. In Hong Kong, you can consult a general practitioner, gynecologist, or visit a Social Hygiene Clinic. Diagnosis typically involves:

Pelvic Examination: The doctor will check for signs of infection.
pH Test: A simple test strip is used to check the acidity of vaginal fluid. A pH level higher than 4.5 is a strong indicator of BV.
Microscopy ("Wet Mount"): A sample of discharge is examined under a microscope to look for "clue cells" (vaginal cells covered with bacteria), which are a hallmark of BV.
Laboratory Tests: a sample may be sent to a lab for more definitive testing.

Treatment and Management Options

BV requires prescription medication; it cannot be treated with over-the-counter yeast infection creams. The primary treatment involves antibiotics that target the overgrown bacteria.

First-Line Treatment:
- Metronidazole: Taken orally as pills (twice daily for 7 days) or used as a vaginal gel (once nightly for 5 days).
- Clindamycin: Available as a vaginal cream (once nightly for 7 days).
Importance of Completion: It is crucial to complete the entire course of antibiotics, even if symptoms disappear sooner, to prevent recurrence.
Partner Treatment: Male partners generally do not require treatment, as treating them has not been shown to prevent recurrence in women.
Recurrent BV: Some women experience BV that returns multiple times a year. For recurrent BV, a doctor may prescribe a longer-term treatment regimen, such as a topical gel used twice weekly for several months.

Potential Complications: Why Treatment Matters

Leaving BV untreated can lead to serious health risks:

Increased Susceptibility to STIs: BV makes the vagina more vulnerable, significantly increasing the risk of acquiring sexually transmitted infections like HIV, chlamydia, and gonorrhoea³.
Pregnancy Complications: BV is associated with preterm birth, low birth weight, and miscarriage⁴.
Risk after Gynaecological Surgery: BV can increase the risk of developing infections after procedures like hysterectomies or abortions⁵.

Prevention Tips for Hong Kong Women

While BV cannot always be prevented, you can reduce your risk:

Avoid douching. The vagina is self-cleaning.
Limit the number of sexual partners and consider using condoms.
Wear breathable, cotton underwear and avoid prolonged wear of tight, damp clothing like yoga pants or swimsuits.
Wipe from front to back after using the toilet to prevent bacteria from the anus spreading to the vagina.

Conclusion

Bacterial Vaginosis is a common but treatable condition. Recognizing the distinct "fishy" odour and thin grey discharge is key to differentiating it from other infections. For women in Hong Kong, seeking a professional diagnosis is essential for receiving the correct antibiotic treatment and avoiding potential long-term health consequences. By understanding BV and adopting simple preventive measures, you can take proactive control of your vaginal health.

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