Scientists at the University of Maryland, Baltimore ask others to explore a hypothesis in which behavior of the pathogen Chlamydia trachomatis may increase risks of female infertility.
BALTIMORE, MD – Scientists are being urged to consider a new paradigm in the basic biology of a pathogen that appears poised to inflict greater harm on public health due to human sexual practices. In a perspective based on historic and geographic patterns of Chlamydia trachomatis, Patrik M. Bavoil, PhD, lead author, chair of the Department of Microbial Pathogenesis at the University of Maryland School of Dentistry (UMSOD) and adjunct professor in the Department of Microbiology and Immunology at the University of Maryland School of Medicine (UMSOM), and colleagues at the University of Maryland, Baltimore pose the question: “Does Active Oral Sex Contribute to Female Infertility?”
In the article, published in The Journal of Infectious Diseases on Nov. 15, 2017, Bavoil and colleagues present a multifactorial hypothesis based on revising the status of C. trachomatis from “principal pathogen to commensal organism/opportunistic pathogen,” which they urge both researchers and clinicians to explore.
Chlamydia is the most frequently reported bacterial genital infectious disease in women in the United States and may be asymptomatic or weakly symptomatic. Left uncured by either antibiotics or the body’s immune system, the infection can result in urethritis, cervicitis, pelvic inflammatory disease (PID), ectopic pregnancy, and infertility, among others. A poorly understood feature of chlamydial infection is that it may persist and go undetected in an infected individual only to reappear sometimes years later.
The authors observe that C. trachomatis transmitted via the fecal-oral or genital-oral routes may colonize gastrointestinal (GI) tract sites without symptoms.
Bavoil and colleagues observe that in human hosts, C. trachomatis that colonizes GI sites may disseminate chronically or episodically to the rectum and feces. Furthermore, rectal C. trachomatis may chronically or episodically contaminate and/or infect the female lower genital tract, exacerbating host responses and contributing to reproductive sequelae.
“In developed, sanitized regions of the world, sexual transmission remains the major route by which C. trachomatis disseminates among men and women. GI tract colonization may, however, be making a comeback with the help of increasing oral sex practices,” the authors state.
They suggest that to safeguard public health, clinicians should be encouraged to go beyond the traditional sampling of urogenital sites by expanding screening for C. trachomatis to rectal and, when appropriate, pharyngeal sites in sexually active adults.
Researchers also urge other scientists to test what they state as a three-part hypothesis: 1) like its veterinary relatives, the oculogenital pathogen C. trachomatis evolved as a commensal organism of the human GI tract primarily transmissible via the fecal-oral route; 2) in the modern era, C. trachomatis causes opportunistic infection at non-GI tract sites under conditions driven by improved sanitation and hygiene; and 3) the rise in the practice of oral sex contributes to the increased prevalence of the pathogen in the human GI tract. Infectious organisms produced in the GI tract can reach the rectum and go on to infect the female urogenital tract, potentially contributing to, among others, PID and tubal factor infertility.