User:Nivetha.karunakaran/Vaginal flora in pregnancy

Microbiota in Pregnancy
During pregnancy, the vaginal microbiome can contribute and play an important role in spontaneous and preterm labor. The transmission of the flora from mother to children occurs via the vagina, breast milk, and the maternal gut. After the mother has given birth to her child, the Lactobacillus-rich microbiome drops significantly, and it becomes more diverse during the postpartum period.

During pregnancy, the pH is altered due to excessive vaginal discharge, and this alters the microbiota that is present in the vagina. The bacterial species Firmicutes and Actinobacteria are identified in dysbiotic states such as this one.

Bacterial vaginosis and pregnancy
A major portion of the vaginal microbiome also includes vaginal viral virome. According studies that have been done so far, it can be seen that there are an abundance of ds DNA viruses, ss DNA viruses and some unidentified viruses that are part of the vaginal microbiome. Only few eukaryotic viruses were detected. Out of the ones that were detected, the pathogenic viruses were Herpesvirales and Papillomaviridae.

Racial variation in microbiomes
There are racial variations that are present in microbiomes between women of different races. Women who belong to Asian, White, and Caucasian race have be observed to have more anaerobic flora. The dominant member in the microbiome of these women is Lactobacillus. Women who are Hispanic and Black have anaerobic bacteria, but the dominant member of their microbiomes is not Lactobacillus. Black females are seen to have single-species dominant cluster, while Caucasian women have multiple species of Lactobacillus present in their microbiome.

Racial diversity is just of the few factors that is known to influence the variation in microbiomes in women. Other factors that also influence the variation in microbiomes are health, sexual partner, mother being a diabetic or not, and variation between monozygotic and dizygotic twins. All of different modes of delivery of microbiome from the mother to the infant, vaginal delivery can be seen to be the most favorable.

Abnormal Vaginal Flora (AVF)
Vaginal microbiomes are affected and influenced by many exogenous and endogenous factors. These factors can include contraceptive agents, using antibiotics, vaginal douching, and pregnancy. Abnormal vaginal flora (AVF) is when there is an overgrowth and colonization of pathogenic microorganisms. This includes microorganisms that cause infections such as vulvovaginal candidiasis (VVC), bacterial vaginosis (BV), cytolytic vaginosis (CV), intermediate flora and mixed vaginitis, and trichomoniasis.

Studies shows that AVF can be one of the contributing risk factors in gynecological complications. There complications include sexually transmitted diseases and pelvic inflammatory disease. AVF has also been associated with issues such as premature rupture of membranes, preterm birth, ascending intrauterine infections, and other adverse outcomes of pregnancy.