Yeast infection, also referred to as vaginal candidiasis or vaginal thrush, is an irritating, fungal condition that occurs when the yeast in the intestinal tract and vagina starts multiplying too fast, disrupting the balance of microorganisms in the area .
It is caused by a common Candida fungus known as Candida albicans . The intestinal tract and vagina naturally contains certain Lactobacillus bacteria and Candida fungi. The bacteria produce some acids that prevent an overgrowth of the yeast, thus maintaining the balance of the vaginal flora . Any disruption of this balance can lead to the symptoms of infection due to a yeast overgrowth .
The changes occurring in your body during pregnancy are believed to be at least partly responsible for making you more prone to the infection . The higher estrogen hormone levels promote the glycogen production in your vagina, resulting in additional glucose in the vaginal secretions which in turn boosts the growth of yeasts. . Some researchers even believe the hormone to directly affect the yeast growth, helping the fungi to stick easily to the vaginal wall .
Apart from the pregnancy related changes, obesity, gestational diabetes and prolonged antibiotic medication (lowers immunity)  are a few possible risk factors that might disturb the bacteria-yeast balance.
About 75% women get the infection at least once in their lives with the incidence rising even higher in pregnancy. So, it is evidently one of the most common pregnancy complaints throughout the world. But despite being so common, it is not counted among the signs of pregnancy as unlike most other symptoms, a yeast infection can lead to certain complications unless treated properly .
In some rare cases, the infection has no detectable symptoms in the early stage and remains undiagnosed until it reaches an advanced stage.
The above measures can help prevent you from getting the infection for the first time as well as keep recurrent yeast infections at bay.
It is an easily curable condition, when treatment begins at an early stage. Diagnosis might involve a physical examination and collection of a sample of the discharge for laboratory testing . Although mild cases can often be treated at home, consulting your doctor is necessary if you suspect a yeast infection while pregnant (especially during the second and third trimesters) as the symptoms might indicate some more serious contagious diseases (e.g. UTI or a sexually transmitted disease) .
There is little or no scientific evidence for proving the efficacy of these natural remedies ; so, it is advisable to check with your doctor or midwife before opting for any of the above.
Your doctor is least likely to prescribe any medication in the first trimester due to their possible association with increased risks of birth defects and miscarriage . So, you might have to manage an early infection at home using the above-mentioned tips and natural treatments.
Creams and suppositories: Over-the-counter antifungal creams and suppositories are usually safe after the initial 3-4 months . Clotrimazole (Gyne-Lotrimin, Canesten) and miconazole (Monistat) are most commonly used for the purpose .
Over-the-counter medicines: Most non-prescription oral antifungal medications are not recommended for pregnant women  as they are suspected to increase the risk of various congenital conditions such as autism.
In most cases, it does not last longer than 1-2 weeks. Make sure to contact your health care provider if the symptoms refuse to go away within a couple of weeks of starting the treatment .
It is just a fungal infection that does damage the vagina or transmit into the uterus and placenta, thus is not usually harmful for the unborn baby . However, having the condition during labor and delivery might cause your baby to develop thrush in the mouth . Thrush in your baby can again transmit the infection to you (breast yeast infection) during breastfeeding.
Watch out for abnormal symptoms like abdominal cramping, contractions, vaginal bleeding or spotting, abnormal yellowish or greenish discharge with or without any distinctive smell, as these might indicate some more serious pregnancy complications.
The ICD-9 codes 112.1  and 616.1  are used for referring to the condition while its ICD-10 codes are B37.3  and N77.1 .