Measuring the Good Bacteria for Urogenital Health

Next-generation sequencing gives researchers an increasingly precise understanding of the balance and diversity of microbes in the urogenital region of the body. In fact, new research conducted with next-generation sequencing challenges many of our assumptions about healthy bacterial presence in the genitals.

For example, doctors often look for pathogens to determine genital health, especially for females. And it’s true that regular STI testing in sexually active adults – as well as testing for E. coli and Staphylococcus –  is vital in maintaining urogenital health.

However, urogenital health in adults can also be measured by looking for and measuring beneficial bacteria. We know that the presence of Lactobacillus in the vagina can be a good marker of vaginal health. It is less well known that determining the amount of lactobacillus in semen can be a marker of health in males.

In an article published in Sterility & Fertility, Lactobacillus was one of the most predominant bacteria in the semen of people described as normal. Another article “showed that the most abundant genera among all samples were Lactobacillus (19.9%), Pseudomonas (9.85%), Prevotella (8.51%) and Gardnerella (4.21%). The proportion of Lactobacillus and Gardnerella was significantly higher in the normal samples, while that of Prevotella was significantly higher in the low-quality samples.”

While medical students are trained to look for numerous characteristics in semen – including sperm count, volume, appearance, odor/smell, viability/mobility, sperm morphology, pH, presence or absence of leukocytes, fructose and other biochemical parameters – the presence and amount of Lactobacillus is not regularly tested. In fact, the presence of bacteria in semen is almost always considered a sign of infection. These new findings challenge our assumptions about what we should teach students to look for, and what is healthy.

My own research conducted with a uBiome academic grant challenges assumptions about vaginal bacteria, particularly in African women. A paper published by Ravel et al (2011), placed North-American females of African descent without vaginal complaints in grade IV vaginal communities, found mainly in Black and Hispanic women, which are classified as non- Lactobacillus dominated and include Gardnerella, Preotella, Corynebacterium, Atopobium, Megasphaera, and Sneathia.

However, my own findings contradict that paper. Most of the Nigerian females tested with 16S rRNA metagenomics without bacterial vaginosis (determined by Nugent score) had Lactobacillus as the most dominant genera (Manuscript under peer-review). In fact, 35 different Lactobacillus species were identified from Non-BV subjects: L crispatus, as the most dominant species, followed by L. iners, L. acidophilus, L. taiwanensis, L. jensenii, and L. gasseri. Even among the BV subjects, the ratio of Lactobacillus to Gardnerella was 1.6:1 on average, and the presence of varying proportions of BV-associated bacteria was similar to studies in other parts of the world.

The next step is to see if probiotics really do help to balance urogenital health, both for males and females. Probiotics are already prescribed to females with urogenital infections. In my research, we plan to use the uBiome’s technology platform to determine whether oral consumption of probiotics designed for prevention of UTIs can be found in voided, clean-catch, midstream urine, as well as in the vagina and the gut.

Kingsley Anukam, PhD, is a visiting associate professor with the Department of Medical Laboratory Sciences, Faculty of Health Sciences, Nnamdi Azikiwe University, Nigeria. He assists in supervising postgraduate students working on microbial metagenomics, and probiotics projects. He has over 80 peer-reviewed publications in the area of probiotics and microbial metagenomics. Currently, he is the Research Coordinator in Endocrinology & Metabolism at St. Joseph’s Health Care, London, Ontario, Canada. In 2016, uBiome awarded Dr. Anukam an academic research grant, and his published findings from the study are available here.