Thrush in pregnancy; points to consider
Vaginal thrush is a common fungal infection by Candida albicans, affecting about 75% of women at some point in their lives.
It is important for women to have timely and convenient access to anti thrush medications as vaginal thrush causes significant vulvovaginitis with whitish curd like discharge, itching, genital swelling and dyspraxia. Treatment is indicated for the relief of symptoms.
In randomised trials both oral and topical antimycotic drugs had similar clinical cure rates (above 90%)
Asymptomatic women and sexual partners do not need treatment.
Vaginal thrush occurs in about 10% of pregnancies. The relative immunosupression, the increased vaginal moisture and high oestrogen levels contribute to this.
Topical azoles, sold above the counter, are the recommended first line agent.
Therapautic Goods Administration has triaged fluconazole as a schedule 3 (pharmacist only) medication, as per poisons standard 2019. ‘Fluconazole in single dose oral preparations containing 150mg or less, for the treatment of vaginal candidiasis.’
Fluconazole is category D medicine (MIMS). Hence not recommended in pregnancy.
Having a discussion with a pregnant woman about the harms versus the benefits of treatment options is important.
Topical azoles are a good therapeutic starting point. It is safe to use a vaginal applicator gently in pregnancy. This has not been shown to cause miscarriage or preterm labour. However, if after a course, symptoms persist please see your maternity clinician as ideally one should establish that there isn’t another diagnosis or cause for this?
A recent Canadian article (Associations between low- and high-dose oral fluconazole and pregnancy outcomes: 3 nested case–control studies) has reviewed a population based cohort with prospective data, over a 7 year period, startling with just under half a million pregnancies.
Pregnant women records that showed:
nil exposure
low dose use (<150mg) , this was about 70% of the group.
high dose use (>150mg) fluconazole groups were reviewed.
The outcomes studied included
spontaneous abortion (we term it miscarriage) Low dose use, adj OR 2.23 95% CI 1.96-2.54, High dose treatment adj OR 3.2 95% CI 2.73-3.75)
congenital malformations (Increased cardiac septal defects detected with group that received high dose fluconazole in early pregnancy, adj OR 1.81, 95% CI 1.04-3.14)
stillbirths (No association found)
Mothersafe is an excellent go to resource for clinicians and patients alike. Oral fluconazole is considered a second line treatment in pregnancy, for patients whose symptoms persist despite adequate topical treatment or for those women who cannot tolerate topical thereapy. In light of this recent article, is it time to rethink this advice? This concept is explored in a recent Australian Doctor article (Miscarriage risk from OTC thrush meds could ‘prompt rethink‘) by Jocelyn Wright, with some input by myself.
1. The study needs replication, and the limitation of missing drug and alcohol information in these cohorts, is an important one.
2. Above the counter medications provide women with quick and convenient access to some medications, helpful towards symptom relief
3. Fluconazole is only an above- the- counter med in a single low dose form
4. My opinion is that pregnant women with thrush like symptoms, should try the first line topical agents which are readily available, however if not resolved in the expected time, see their health professional so they can be reviewed/vaginal swab obtained and details regarding risk benefit ratios of second line agents discussed to enable informed management decisions.
