Written by Dr Goh Lit Ching
Vaginal discharge is normal fluid or mucus produced by the female organ to keep the reproductive system healthy. Vaginal discharge in women can happen due to normal physiological reason, as well as in pathological causes.
Types of vaginal discharge
Normal physiological discharge often changes with the menstrual cycle.
During mid cycle ovulation, the discharge may appear to be clearer, with a stretchable consistency. After ovulation (during luteal phase), the discharge can be thicker and slightly yellowish.
The volume of vaginal discharge can also increase during higher oestrogen states, such as during ovulation, puberty and pregnancy. Vaginal discharge can also increase in women on oestrogen-based therapies such as birth control pills.
Some women may present with perpetual vaginal discharge at all times of their menstrual cycle without any underlying reason, and the incident rate is about 10% for those who present with such condition.
There could be several causes for pathological vaginal discharge. The presenting complaints from patients seeking help regarding vaginal discharge can be related to the volume, colour, odour, or other associated symptoms such as itch and rash.
Abnormal vaginal discharge is most commonly caused by vaginal infection. According to statistics published by Singapore Medical Journal (SMJ) in year 2020, about 70% of all causes are associated with these three infections – Bacterial Vaginosis (BV), Candidiasis or Trichomoniasis. Out of the three, BV is the most common and accounts for up to 50% of all infections. Some of the other commonly detected infections include sexually transmitted diseases (STDs) such as Chlamydia Trachomatis and Neisseria Gonorrhoea. The reason that they are not as commonly picked up in symptomatic women is because STDs may be asymptomatic and produce no discharge at all.
Below are a few examples of how vaginal discharge can be categorised based on commonly presented scenarios in our womens’ health clinic:
What Is Considered Abnormal Vaginal Discharge?
1. Colour of the discharge
White thick curdy discharge is mostly associated with vulvovaginal candidiasis infection. It is usually associated with other skin symptoms, such as itch and redness. Some patients may experience burning sensation as well if the inflammation is severe.
- Yellowish / Greenish
Yellowish or greenish discharge can be due to bacterial vaginal infections, or a change in vaginal PH and vaginal environmental flora. More investigations such as vaginal swab test is needed before the causes are confirmed. Most commonly, Bacterial Vaginosis (BV) and some STDs such as Trichomoniasis can cause this kind of discharge.
Greyish discharge with offensive odour can happen in Bacterial Vaginosis (BV) infection
Brownish discharge is usually due to a mix with spotting of blood from the vagina. There can be many causes of spotting. Physiological cause includes intermenstrual bleed caused by ovulation; while pathological causes can be due to underlying hormonal imbalance conditions, vaginal infections such as STDs, or structural abnormalities in the cervix, uterus or ovaries such as fibroids, polyps, or cysts. More investigations such as pap smear, blood tests or imaging scans will be needed to ascertain the underlying causes.
2. Smell / Odour
Odour is more noticeable when there’s any change in vaginal PH or flora. Non offensive mild odour can be purely physiological, or noticeable in some candidiasis infection. Offensive odour, especially those described as ‘fishy smell’, can be due to Bacterial Vaginosis (BV) or STDs such as Trichomoniasis infection.
3. Changes on skin surface
- Itch and redness
This is commonly associated with vaginal infections such as candidiasis, or STDs; especially when there’s concurrent vaginal discharge. Some skin conditions such as eczema or contact dermatitis can also cause similar presentation. It is important to go for more investigations to differentiate between these causes.
Other than conditions described above, parasitic infection such as scabies infection can also cause rash around the genitalia area.
Blisters and vaginal discharge can be due to Herpes Simplex Virus Infection (HSV). It is a type of commonly sexually transmitted infection. Some patients can stay asymptomatic even after infected. Any new onset of blisters should be checked in the medical clinic.
Treatment For Abnormal Vaginal Discharge
Treatment depends on the underlying causes of vaginal discharge.
Physiological discharge may not need any intervention. If the discharge is due to vaginal infection such as candidiasis, antifungal treatment is needed. If it is due to Bacterial Vaginosis or other STDs, antibiotic or antiviral treatment may be needed. For STDs cases, there will also be a need of follow up review to make sure the infection is cured and not transmitted to the sexual partner. If the discharge is due to other underlying structural abnormality or hormonal imbalance, the use of hormonal medications or intervention of underlying structural abnormality may be needed based on the severity of each individual clinical scenarios.
Sometimes, vaginal discharge can become a recurring condition. It is therefore important to maintain a healthy lifestyle, and a good vaginal health with a balanced PH level to further minimize the recurrence of opportunistic infections. Avoiding vaginal douching, usage of local irritants or perfumed products, and wearing of tight-fitting synthetic clothing may help for long term maintenance.
Take Home message
In summary, vaginal discharge can either be a normal physiological occurrence or a pathological manifestation. It is therefore important to differentiate between these two groups because the treatment methods vary.
Any history of a change from the usual pattern of vaginal discharge in a woman is an important differentiating factor and should be explored further with a consultation in the clinic.
Also check out: Our blog on sexual health