diflucan-lPregnant women are at increased risk of suffering from vaginal candidiasis or thrush.  According to CDC, on the whole, 75 percent women suffer from thrush at sometime or the other of their lives, often more than once. However, during pregnancy as many as 30-32 percent women suffer from candidiasis thanks to higher sugar levels and the greater moisture in the vaginal environment. Additionally the vagina becomes more alkaline than acidic, making it more prone to thrush.

Often thrush becomes a constant problem during pregnancy and this is compounded by the contraindication of many drugs during pregnancy. Doctors avoid giving even relatively safer drugs and thrush is usually treated by local and topical medicines to prevent any possible problems. However, there are some cases of thrush that do not respond to topical treatments. In such cases anti-fungal drugs given orally like flucanozole are prescribed would be prescribed, except that the drug carries an FDA warning against use during pregnancy.

FDA warning on Diflucan (flucanozole)

Thanks to many case reports published in medical publications of birth defects in the children of mothers who had taken Diflucan during pregnancy, the FDA issued warnings against its use in 2011. These warnings were against the long-term use of the drug in high doses ranging from 400-800 mg. a day as it caused rare and distinct birth defects when taken during the first trimester. The side effect on the infants included brachycephaly, abnormal facies, abnormal calvarial development, cleft palate, femoral bowing, thin ribs and long bones, arthrogryposis and congenital heart disease.

The human studies showed the same results as the effects of the drug on animals during earlier animal studies.  However, there were no long-term studies or large studies that showed whether flucanozole in lower doses caused any birth defects or not. The drug was categorized as category D for pregnancy in high doses; the low dose one was permitted only after weighing the risks and that, too, in a single dose.

Latest research debunks this warning

Ditte Molgaard-Nielsen, an epidemiologist at the Statens Serum Institute in Copenhagen and his team collected data on more than 7,300 women who took flucanozole during their pregnancies. They found that 210 infants were born with birth defects. The other group consisted of more than 968,000 women who did not take flucanozole and served as the control group. Of this group, 25,000 babies were born with birth defects. In both groups the risk factor remained a steady 0.6 percent, showing that flucanozole did not contribute to birth defects. This report was published in the Aug 29, 2013 issue of the New England Journal of Medicine.

However, there is evidence to show that the drug is linked to increased risk of a rare congenital heart problem called tetralogy of Fallot in the baby. The researchers studied 15 birth defects and concluded that 14 of those were not linked to increased risk after taking flucanozole, but one was. Molgaard-Nielsen suggested that further studies were required to confirm this link. However, flucanozole was not linked to craniosynostosis (a defect in the baby’s skull), middle ear defects, cleft palate, cleft lip, limb defects, an abnormal number of finger or toes, fused fingers or toes, diaphragmatic hernia, heart defects and shifting of a lung to which it had been earlier linked.

Does this mean that doctors will now prescribe the drug during pregnancy?

It is not likely that doctors are going to rush to prescribe this drug during pregnancy, because even if the risk is very small, the risk exists. The first line of treatment for thrush is topical treatment, including local pessaries, ointments and creams; as there are many different drugs available for this, if one does not work, the doctor can prescribe another one. Then, if the infection does not come under control, there are other drugs including many over the counter ones as also natural remedies that are quite effective. In the rare cases that flucanozole treatment is required, the doctor will give it in the smallest possible dose for the shortest possible time. In any case, thrush during pregnanacy needs to be shown to a doctor and medicines taken under medical advice only.

Other dietary interventions that are safe are eating more of probioticis and yoghurt in an attempt to restore the normal flora in the body, wearing loose clothing, reducing refined foods and sugar in the diet. It is also important to rule out bacterial vaginosis which has similar symptoms but needs a different line of treatment.  Occasionally thrush may not even present symptoms, but it still needs to be treated as it can cause higher spontaneous preterm birth rate if untreated.

Sources:

FDA

New England Journal of Medicine