Why pregnant women are more likely to get thrush

thrush pregnancy

Thrush, otherwise known as candidiasis, occurs when there is an overgrowth of the fungi (yeast) that naturally occurs on the skin. Technically, thrush is an infection caused by a strain of fungi called Candida. Vaginal thrush occurs when this overgrowth of candida occurs in the woman’s vagina, or the area surrounding it, the vulva.

Most women suffer from thrush at some point in their life. It is most common during pregnancy, but can occur at any age, whether or not a woman is pregnant. Typically, during a bout of thrush, the vaginal area may feel itchy or sore. Often, women may experience some localised stinging or discomfort when passing urine, and there may be a curdy, white vaginal discharge too.

Why does pregnancy increase your chances of thrush?

During pregnancy, women are thought to be up to twice as likely to develop thrush than at any other age.1 This is thought to be due to the increased circulating oestrogen levels that are present during pregnancy, which provide optimal conditions for the growth of candida. Interestingly, thrush is also more common in women who are on the combined oral contraceptive pill and hormone replacement therapy for the same reason.2

Studies have shown that up to 30-40% of women who are pregnant actually may have thrush at some point in their pregnancy, although many of these women may have no symptoms. Women are usually only offered treatment if they develop symptoms though.3

Thrush is an extremely common occurrence in pregnancy, and not something that most women should worry about unduly. Studies have found that there does not appear to be any association between candida (thrush) and babies being born prematurely, or of low birth rates.4

So, the effects of thrush are more likely to be annoying or uncomfortable rather than dangerous to your pregnancy. If you experience symptoms of thrush during pregnancy, it is important to seek medical advice.

Treatment for thrush

It is important to seek medical advice from your doctor or pharmacist when it comes to taking any medications or using any remedies during pregnancy.

When treating thrush, most topical medications (creams and pessaries that are applied to the area) are safe in pregnancy, but oral antifungal tablets such as fluconazole must be avoided because they can cause pregnancy complications in some women. Fluconazole should be avoided when breastfeeding as well.

The best treatments to try first in pregnancy are either clotrimazole pessaries or cream, or ketoconazole cream as they have long been used in pregnant women without any adverse effects. Your doctor will explain which treatment is the most suitable for you however, and these medicines should only be used during pregnancy under the supervision of a doctor or midwife. As such, don’t just go and buy it over the counter, but go and check with your doctor first.

When thrush occurs during pregnancy, it often may take longer to resolve than at other times. Therefore, that current advice is for treatment to go on for 7 to 14 days, rather than 1 to 3 days that is usually adequate at other times.

You should see your doctor again if your symptoms do not fully resolve within 7 to 14 days, or you are concerned, or your symptoms change. Women who have symptoms of irritation around the vulva may be prescribed a cream to use in this area alongside the pessaries or internal creams.

When pregnant, it is important to use pessary applicators carefully to avoid any damage to the cervix. If you are worried, some women find it easier to just use a clean finger to insert the pessary instead.

If your sexual partner has symptoms then they should be treated as well, but there is no need for them to receive precautionary treatment if they are symptomless.

What if thrush treatment does not seem to work?

Sometimes, you may still have symptoms following treatment. Often this is because the treatments sometimes cause irritation themselves, which can be mistaken for a continuation of thrush. If the symptoms are mild, it is worth waiting a few days after completing treatment to see if things improve.

If you are still experiencing a number of symptoms, your doctor or nurse may take a swab to see if thrush is still present, and if so what type. This will give your doctor suggestions on the best treatment as well. They may also check that it is not a different infection causing the symptoms.

If things are improved but not completely resolved, your doctor may suggest a second course of treatment.

If your discharge is an unusual colour (for example, a green or brown shade), or has an offensive smell, then this is not thrush, especially if you have had recent unprotected intercourse. Symptoms such as bleeding after intercourse should not be put down to thrush either unless other conditions have been ruled out by a doctor. Potentially, they may be a sign of a different infection or something more serious, so ensure you get checked by your doctor.

What can you do to avoid getting thrush during pregnancy?

There are some simple lifestyle changes you can make to reduce your chances of getting thrush. These include avoiding using soaps, shower gels, and feminine hygiene products in the vulval area, and just using water and a soap substitute (for example, a gentle, unscented moisturiser such as aqueous cream). The area should be washed once a day and vaginal douching should be avoided.

It is thought that the use of biological washing powders and fabric conditioners to wash underwear may increase the risk of thrush, so changing to a non-biological washing powder and stopping the use of fabric conditioner when washing underwear may help. The avoidance of tight fitting or non-absorbent clothing is thought to be beneficial too.5

Even if the above suggestions are followed, you may still find you develop thrush as in some women it can be difficult to avoid. Unfortunately, if you get thrush once during pregnancy it can often return, but using treatments on the advice of your doctor can help you feel more comfortable.

References

  1. T. Bauters et al., ‘Prevalence of vulvovaginal candidiasis and susceptibility to fluconazole in women’, American journal of obstetrics and gynaecology, Vol. 187, No. 3, 2002, pp. 569-574.
  2. Ibid.
  3. J. D. Sobel, ‘Vulvovaginal candidosis’, The Lancet, Vol. 369, No. 9577, 2007, pp. 1961-1971.
  4. M. F. Cotch, ‘Epidemiology and outcomes associated with moderate to heavy Candida colonization during pregnancy. Vaginal Infections and Prematurity Study Group’, American Journal of Obstetrics & Gynecology, Vol. 178, No. 2, 1998, pp. 374-380.
  5. BASHH, ‘National guideline on the management of vulvovaginal candidiasis’, British Association for Sexual Health, [website], 2007, https://www.bashh.org/documents/1798.pdf, (accessed 8th January 2018).

Dr. Jennifer Kelly MBChB(hons) MRCGP DRCOG

Jennifer is a General Practitioner, medical writer, parent, and founder of the Grace Kelly Ladybird Trust, registered charity for childhood cancer awareness and research (www.gracekellyladybird.co.uk). She also has a particular interest in women’s and children’s health, and enjoys medical writing, particularly helping make medical information easily accessible to those who want to find out more.

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