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.

References:

http://journals.lww.com/co-clinicalnutrition/Abstract/2009/11000/Targeting_the_vaginal_microbiota_with_probiotics.5.aspx

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0105998#abstract0

http://www.ncbi.nlm.nih.gov/pubmed/19833694

http://www.ncbi.nlm.nih.gov/pubmed/?term=abnormal+vaginal+microbiota+and++pregnancy

http://jcm.asm.org/content/45/9/3145.short

http://journals.lww.com/co-clinicalnutrition/Abstract/2009/11000/Targeting_the_vaginal_microbiota_with_probiotics.5.aspx

Maternal ZIKA virus infection linked to fetal and placental malformations, apart from Microcephaly.

The World Health Organization has declared the Zika virus an international public health emergency, with a prediction of about four million people being infected at the end of the year.

WHO has issued a travel warning for pregnant women advising them not to travel to areas with continuing outbreaks of Zika virus due to the potential risk of birth defects.

Sexual transmission appears to be more common than previously thought of. "Pregnant women whose sexual partners live in or travel to areas with Zika virus outbreaks should ensure safe sexual practices or abstain from sex for the duration of their pregnancy," the WHO said, based on advice from its Emergency Committee of independent experts.

According to a preliminary report of case series  from Rio de Janeiro, Brazil, published online March 4 issue of the New England Journal of Medicine, ZIKA is also linked to fetal death, placental insufficiency, IUGR and Nervous system malformation.

Dr. Patrícia Brasil, MD, the principal investigator of the study  “our findings provide further support for a link between maternal ZIKV infection and fetal and placental abnormalities that is not unlike that of other viruses that are known to cause congenital infections characterized by intrauterine growth restriction and placental insufficiency.”

In September, 2015 researchers in Brazil identified dengue like fever, which was later identified as ZIKV. In the same month the ZIKV was linked to microcepahy, cases in Brazil rocketed to 3,500 from 147, the average for the same time last year (2014).

The link was first detected when Brazilian health authorities found traces of the Zika virus in a deceased infant born with microcephaly or in amniotic fluid of mothers delivering microcephalic infants.

In the present study, the researchers enrolled pregnant women of any gestation, who presented with a rash that had developed within the previous 5 days. Out of 88 women, 72 (82%) women tested positive ZIKV in blood and/or urine by reverse-transcriptase polymerase chain reaction assays. The researchers followed the women prospectively with clinical examinations and serial ultrasound. All the study participants were generally healthy with no h/o congenital malformations.

Clinically the women presented with a macular or maculopapular rash, pruritus (94%) arthalgia (65%), conjuntival redness (58%). Fever was not a significant symptom with only one third of women reporting it.

All the ZIKV negative as well as positive women had ultrasound. USG showed abnormalities in 12 of ZIKV positive women while those women who are negative showed normal USG.  Sonographically detected abnormalities include:

• intrauterine growth restriction, with or without accompanying microcephaly(5)
• cerebral calcification (4)
• CNS alterations (n = 2)
• Oligohydramnios and anhydramnios (2)
• Abnormal arterial flow in the cerebral or umbilical arteries(4)
• additional malformations, including agenesis of the vermis, Blake’s pouch cyst, and potentially a club foot, in addition to cerebral calcifications, intrauterine growth restriction, and microcephaly(1)

Abnormalities were present in fetuses of women irrespective of there gestational age at ZIKV infection, although those women infected in first trimester show signs of insult during embryogenesis. CNS abnormalities seen in fetuses infected as late as 27 weeks.

Six live births and two still births occurred during the follow up and confirmed the Sonography findings.

The authors suggest that “many aspects of ZIKV infection are similar to those of rubella, particularly rash, arthralgias, pruritus, and lymphadenopathy in the mother without high fever.” But, it is worrisome that there is no population immunity for ZIKV as compared to rubella U.S. pandemic of 1959–1965, when only 17.5% of women of childbearing age lacked rubella antibodies.

In summary the study findings provide support to the hypothesis of link between maternal ZIKV infection and fetal and placental abnormalities. The women infected with ZIKV should be followed up closely with serial ultrasonography to evaluate for signs of placental insufficiency, given the risks of fetal death and intrauterine growth restriction.

References:

http://www.who.int/mediacentre/news/statements/2016/zika-ec/en

http://www.nejm.org/doi/full/10.1056/NEJMoa1602412?query=featured_home#t=articleDiscussion

 

Managing Menopause: Is it time to take a second look at the Women's Health Initiative (WHI) study results?

Menopause is an important life event for a woman that signifies the end of her reproductive era and transitioning into a period of increasing health risk from cardiovascular disease, osteoporosis, and other chronic diseases.

According to a census in 1998, there were more than 477 million postmenopausal women in the world, and the number is going to rise to approximately 1.1 billion by 2015. Life expectancy for women worldwide was 65 years in 1998 which has currently increased to 73.2 years (81 years in developed countries).  With increasing life expectancy women spend one third of life in this phase of life.  

In the year 2000, there were an estimated 45.6 million postmenopausal women in the United States, out of which about 40 million were older than age 51, the average age of natural menopause in the Western world.                                    

According to a book chapter by Dr.  JoAnn E. Manson, MD, DrPH professor of medicine at Harvard Medical School and Brigham and Women's Hospital “Aging of the female reproductive system begins at 20 weeks gestation with regard to follicle atresia and proceeds as a continuum. It consists of a steady loss of oocytes from atresia or ovulation, and does not necessarily occur at a constant rate. Because of the relatively wide age range (40-58 y) for natural menopause, chronologic age is a poor indicator of the beginning or the end of the menopause transition.

This article is based on a perspective by JoAnn E. Manson, M.D., Dr.P.H., and Andrew M. Kaunitz, M.D. in March 03, 2016 edition of  The New England Journal of Medicine( NEJM).

Menopausal symptoms are well tolerated by some women, but may be very troublesome to other women. Often there is underreporting of menopausal symptoms due to cultural taboos. The attitude towards menopause varies according to culture and ethnicity, with 80% African women reporting symptoms versus very few Asian women reporting symptoms.

There has been an ongoing confusion regarding the findings of WHI study and prescription of hormonal therapy to relieve the symptoms of menopause.

The Women's Health Initiative (WHI) was launched in 1991 and consisted of a set of clinical trials and an observational study, which together involved 161,808 generally healthy postmenopausal women.

The clinical trials were designed to test the effects of postmenopausal hormone therapy, diet modification, and calcium and vitamin D supplements on heart disease, fractures, and breast and colorectal cancer. The trials were specifically designed to address questions about effect of initiating menopausal hormone therapy for the prevention of chronic disease in postmenopausal women across a broad range of ages, including many women in their 60s and 70s?

In 2002, the study results ripped the widely held belief that hormone replacement therapy protected women from heart disease and other chronic illnesses.  Instead, the Women's Health Initiative study found concluded that taking estrogen plus progestin hormone replacement therapy — HRT — actually increased a woman's risk of heart disease and breast cancer.

Within months of the results, number of women using HRT dropped by half. 

The results of the study were extrapolated to women in 40s and 50s who had severe vasomotor symptoms disrupting quality of life. In-fact, these women had trouble finding clinician who could prescribe them with HRT.  

But, studies conducted during Extended Poststopping Phases of the Women’s Health Initiative Randomized Trials when broken down according to age groups showed entirely different outcomes. Subgroup analysis stratified according to age and time since menopause onset modified the effect of HRT on some of the outcomes. The study concluded that HRT is a reasonable option for the management of moderate to severe menopausal symptoms among generally healthy women during early menopause.

In-fact, the USPSTF in its recommendation made a specific mention that “This recommendation applies only to postmenopausal women who are considering hormone therapy for the primary prevention of chronic medical conditions. This is not a recommendation about the use of hormone therapy to treat menopausal symptoms, such as hot flashes or vaginal dryness; the USPSTF did not review the evidence related to this possible indication because it falls outside of the mission and scope of the USPSTF. This recommendation also does not apply to women younger than 50 years who have had surgical menopause”.

The North American Menopause Society (NAMS), the Endocrine Society, the American College of Obstetricians and Gynecologists (ACOG) endorse the use of HRT in younger women for treating postmenopausal symptoms, who do not have specific contraindication for the therapy.

This will definitely improve the quality of life and it is quite likely that the benefit would outweigh the risks.

These organizations have many resources that help clinicians in decision making, the NAMS have a MenoPro Mobile App, which helps in personalization of treatment to individual patient and help patient in shared decision making.

The MenoPro app has several unique features, including the ability to calculate your 10-year risk of heart disease and stroke, which is important in deciding whether a treatment option is safe for you. It also has links to online tools that assess your risk of breast cancer and osteoporosis and fracture.

Photo courtesy: NAMS

Finally Dr. JoAnn E. Manson emphasized the need of training young healthcare providers to keep up with the variety of options in treating postmenopausal women. This will certainly help in improving the quality of life of a growing population.

References:

Manson JE, Kaunitz A. Menopause management: getting clinical care back on track. N Engl J Med. 2016;374:803-806.

https://www.google.com/?gws_rd=ssl#q=current+life+expectancy++in+world+

http://www.menopause.org/docs/2012/cg_a.pdf?sfvrsn=2

http://www.npr.org/sections/health-shots/2013/10/04/229171477/the-last-word-on-hormone-therapy-from-the-womens-health-initiative

http://jama.jamanetwork.com/article.aspx?articleid=1745676

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