Women may present in a variety of settings (general practice, gynaecology, family planning or genitourinary medicine) with a complaint of vaginal discharge. There is no standard definition that differentiates a normal vaginal discharge from one that may be considered abnormal. However, an excessive or unpleasant vaginal secretion, with or without associated pruritus or genital odour, may be categorized as a working definition for an abnormal vaginal discharge.
Content of normal vaginal discharge
Physiological vaginal discharge is a conglomeration of secretions from various sources, including the vulva, Bartholin’s glands, Skene’s glands, vaginal transudate, cervical mucus and endometrial and tubal fluids. Cervical mucus is, however, the major component.
The amount and nature of the vaginal discharge varies with the age of the woman and the stage of her reproductive life, and in women of reproductive age, it varies with the phase of her menstrual cycle.
Vaginal secretions are normally acidic (pH 3.5-4.5) due to high lactic acid levels; the acid being formed by lactobacilli from the glycogen in vaginal epithelial cells. The acidity is maximal at birth and around the time of ovulation, and is minimal during childhood and post-menopausally.
Causes of vaginal discharge
- – pre-menstrually
- – around the time of ovulation
- – in the puerperium
- – post-abortal or post-termination of pregnancy.
• Associated with use of contraceptives
- – combined contraceptive pill
- – intrauterine contraceptive device.
• Non-infective microbial causes of discharge:
- – bacterial vaginosis (bacterial vaginosis)
- – vaginal candidiasis.
• Sexually transmitted infections
- – Neiserria gonorrhoeae
- – Chlamydia trachomatis
- – Trichomonas vaginalis (Trichomonas vaginalis).
• Less common infective causes of discharge
- – genital herpes
- – genital warts.
• Rare infective causes in the UK
- – syphilitic chancre
- – chancroid
- – granuloma inguinale.
• Associated gynaecological pathology
- – cervical lesions
- – cervical ectropion
- – cervical polyps
- – cervical neoplasia
- – trauma to the genital tract.
• Neoplasia of the genital tract
- – vagina
- – cervix
- – endometrium
- – fallopian tubes.
• Allergies to
- – soaps
- – deodorants
- – fabric conditioners.
• Retained foreign bodies in the genital tract
- – tampons (and toxic shock syndrome)
- – condoms.
The following may be helpful in eliciting the cause of the discharge.
- • Details of discharge: duration, consistency, odour, associated itchiness/soreness. For example, a smelly discharge could indicate bacterial vaginosis or Trichomonas vaginalis, an itch could suggest thrush or Trichomonas vaginalis.
- • Last menstrual period (LMP) and menstrual history including menstrual cycle, intermenstrual and post-coital bleeding. If bleeding is irregular, this could suggest chlamydia.
- • Obstetric history, including recent miscarriage, delivery or termination of pregnancy.
- • Abdominal/pelvic pain, dyspareunia, urinary symptoms.
- • Previous cervical cytology.
- • Past medical history: exclude diabetes, other immunosuppressive states.
- • Sexual history.
Examination and diagnostic tests
- • Thorough assessment of the external genitalia including inguinal nodes and vulva. For example, enlarged, tender inguinal nodes and a watery discharge could suggest herpes.
- • Speculum examination to assess character of discharge.
- • Assessment of vaginal pH. Useful if no access to on-site microscopy. pH above 4.5 would suggest bacterial vaginosis or Trichomonas vaginalis.
- • High vaginal swab for microscopy and culture (lab will test for bacterial vaginosis, yeast and Trichomonas vaginalis).
- • Cervical swab for gonorrhoea culture.
- • Cervical swab for chlamydia test.
- • Pelvic examination. May yield information in cases of upper-genital tract infections or associated gynaecological pathology.
This depends on the cause. See the relevant sections for your suspected or confirmed diagnosis.
Physiological discharge can often be misconstrued as abnormal by women particularly if there has been a recent regretted sexual encounter: discussing this with the patient can often allay her anxieties.