Wednesday, March 9, 2016

Abnormal Vaginal Microbiota: Could it hinder IVF success rates?


Human vaginal microbiota (VMB) plays an important role in women’s health. Since the report (and discovery) of Lactobacillus (Döderlein Bacillus) as common inhabitants of the human vagina in 1892 by Gustav Döderlein,it  is known to play an important role in urogenital health. It has been known since quite long that most vaginal microbiota (VMB) undergoes compositional changes thought out lifetime of women from puberty to menopause, and sex hormone steroids play an important in its stability and composition.

It contributes to low vaginal pH (<4.5) by production of lactic acid, which limits the growth of pathogenic bacteria.

The development of culture-independent profiling methods to detect fastidious or non-cultivable organisms through the analysis of the sequence of marker genes, such as the 16S rRNA gene, has precipitated a revolution in biology and medicine, by spurring projects such as the National Institutes of Health (NIH)-funded Human Microbiome Project, the European MetaHit project and the creation of the International Human Microbiome Consortium.

Culture-independent characterization of bacterial communities have established that at least six types of vaginal microbiota exist, referred to as community state types (CSTs). Four of these CSTs are most often dominated by one of four Lactobacillus spp. commonly found in the vagina (L. crispatus, L. iners, L. jensenii and L. gasseri), while the remaining two lack substantial numbers of Lactobacillus spp.

Disruption of Lactobacilli predominant VMB can lead to growth of abnormal vaginal pathogens. Bacterial vaginosis (BV) represents the most common vaginal syndrome characterized by  lactobacilli being  replaced by Gardnerella vaginalis, Atopobium vaginae, Prevotella , Sneathia, Ruminococcaceae, Parvimonas, Mobiluncus , Veillonella, Megasphaera and other anaerobic microorganisms  which are difficult to culture. BV is not highly inflammatory and is therefore often asymptomatic; this is why it is referred to as a vaginosis and not vaginitis.The clinical symptoms are minimum or insignificant, so BV is often overlooked.

In clinical settings, BV is typically diagnosed using Amsel criteria (three of the following four criteria should be present: 1) clue cells on wet mount microscopy; 2) a ‘fishy’ odour after adding 10% KOH to vaginal secretions; 3) vaginal pH>4.5; and 4) thin, homogenous vaginal discharge) .In research settings, BV is also often defined by Gram stain Nugent scoring, which is based on microscopic visualization of three bacterial morphotypes (a Nugent score of 0–3 is considered normal, 4–6 intermediate microbiota, and 7–10 BV) .

According to a recent paper published online in Journal of Human Reproduction Haahr T et al, the principal author and an MD/PhD student at Aarhus University in Denmark,postulated that Abnormal Vaginal Microbiota may be contributing factor for negative outcome in IVF patients. He further added that about 1 in 5 women suffer from BV and it could affect the fertility.

A total of 130 women were recruited who were seeking IVF treatment, vaginal swab collected from posterior fornix, gram stained and analyzed according to Nugent’s criteria. Real-time polymerase chain reaction (qPCR) to identify the type of bacteria was also used. The researchers compared the results of Nugent scores and results of qPCR to identify abnormal vaginal microbiota and its possible role in IVF success rates.

According to Nugent criteria the prevalence of BV was 21%( 27/130), whereas qPCR identified  abnormal VMB in 28% (36/130) patients with a predominance of  Gardnerella vaginalis and/or Atopobium vaginae. The qPCR have a sensitivity and specificity of 93%.

A total of 84 patients completed the treatment with clinical pregnancy rate of 35% (29/84). Interestingly, only 9% (2/22) with qPCR defined abnormal vaginal microbiota obtained a clinical pregnancy (P = 0.004).

The study is limited by small sample size and Caucasian only subjects. Dr. Haahr says that it is very early to draw any conclusion from the study, but physicians who have patients of recurrent pregnancy loss should investigate them for BV.

Dr. Haahr told Reuters health that “"Several attempts to find the right clinical management or treatment for bacterial vaginosis has shown that this is very difficult, because it seems that a biofilm is growing in the presence of these bacteria,” He and his colleagues are planning a clinical trial in which they will test the effects of treating BV with antibiotics, followed by probiotics, on IVF success. "Hopefully with this new study we might offer these patients help in bettering their pregnancy rates," he said.

Dr. Peter Humaidan of the Fertility Clinic at Skive Regional Hospital and Aarhus University, senior author of the new study was very hopeful of the results of the study and told Reuters Health in a telephonic interview “Probiotic treatments are gaining a wide usage all over the body. So maybe probiotics will be the future, rather than antibiotic treatment." It's possible, he added, that the health of the vaginal microbiome could also influence natural fertility rates.

Other study results suggest that BV infection is associated with infertility and its absence leads to pregnancy, emphasizing its screening and treatment.

According to a paper published in Seminars in Reproductive Medicine by Sirota et al  Studies that characterize the vaginal microbiome in assisted reproductive technology support the hypothesis that colonizing the transfer-catheter tip with Lactobacillus crispatus at the time of embryo transfer may increase the rates of implantation and live birth rate while decreasing the rate of infection.

However, antibiotic treatment before IVF has been shown to be positively disadvantageous for IVF by encouraging other organisms.

Exogenous strains of lactobacilli have been suggested as a means of re-establishing a normal healthy vaginal flora. Carefully selected probiotic strains can eliminate BV and also exert an antiviral effect, thus reducing viral load and preventing foetal and neonatal infection. The administration of beneficial microorganisms (probiotics) can aid recovery from infection and restore and maintain a healthy vaginal ecosystem, thus improving female health also in relation to reproductive health.




















3 comments:

  1. Nice post and thanks for sharing. If you are planning Infertility Treatment in Punjab then must visit Eva Hospital- IVF Centre . Our clinic has served thousands of patients with best results.

    ReplyDelete
  2. Nice Blog Thanks For Sharing Details For More Details About success rate of ivf Process click here

    ReplyDelete
  3. My name is Angelo Alex I was tested HIV/Herpes positive and I was so worried am I going to die soon. I made my search on herbal remedy for Std, then I found lots of testimonies on how Dr James  Herbal Medicine Cured HIV/Aids, and other diseases like,Yeast infection, Rectum  effects, intestine damage, bowel obstruction, Ovarian disease,  Cancer, hypothyroidism, Herpes, COPD, HIV, Arthritis, Lyme disease,Hpv, Infections,Liver Disease, Autoimmune Diseases, Parkinson's disease,Lupus,Nephrology and Hypertension, Neurology, Obstetrics, Gynecology, and Women's Health, Oncology, Pediatrics, Pulmonary, ACUTE MYELOFIBROSIS, ALZHEIMER's symptoms, BREAST CANCER, DIABETES, HAIR LOSS AND HAIR TREATMENT, KIDNEY DISEASES, LEUKEMIA, MYELOID LEUKEMIA, STEM CELL TREATMENT   On websites sharing their testimonies, which made much more sense to me. All the authors pronounce Dr James As a man with Good Heart, I picked interest in their testimonies and I contact him about my situation then he gave me procedure how it works, I proceed after one week he courier his Herbal Medicine to me and instructed me on how to drink it for two weeks to cure. I received His Herbal Medicine so I drank it for two weeks as I was told then after 2 weeks of drinking his medicine, I went for a test I found out I was cured from HIV/Aids & Herpes Virus, I pay homage to him 2 months ago to his country to celebrate with him on his African festival which he told me it usually happens every year. I know there are lots of (HIV)/Aids Herpes Virus denials of Herbal Remedy movement the same few doctors and they represent a very small fraction of the community. I could have died because I refused Natural Herbs Cures for so long, but luckily, by the grace of God I am alive to tell my story. Contact Info...Whatsapp Number...+2348152855846,Email...drjamesherbalmix@gmail.com 

    ReplyDelete