Impact of Candidiasis on Human Infertility
Nadja Melo (GB)
[Melo] Wales Fertility Institute
Few studies have investigated prevalence of Candida species in an asymptomatic cohort of both men and women, and the impact on infertility. Vaginal candidiasis affects 75% of all women at least once during their life. Recent studies show that Candida influences spermatozoa quality suggesting an impact on infertility. This study characterised Candida colonisation in fertile and infertile couples in the oral cavity (saliva) and reproductive tract (semen or vaginal swab). Candida prevalence and diversity from the oral and female/male reproductive tracts of 20 couples (40 individuals) were determined by genetic amplification and pyrosequencing were used to identify Candida species. Multilocus sequence typing analysis was used to assign sequence type among the culturable C. albicans isolates. Candida species were present in the oral samples of 93% of the women, however only 43% of men were colonised. C. albicans accounted for 73% and 57 % in women’s and men’s oral samples, respectively. Interestingly, shared species were observed in oral samples of only three couples. Candida colonisation in semen was lower 6%, in comparison with 37% in vaginal samples. C. albicans (66.6%) was the predominant species in the vaginal samples, unlike oral samples, reproductive samples were colonised only with C. albicans, C. guilliermondii and C. parapsilosis. Only one couple of the 16 studied shared Candida albicans across all body sites. However, genetic analysis identified a greater intra-species diversity in oral and reproductive tract isolates. These findings suggest a higher diversity of Candida in oral but not the reproductive tract isolates. In vitro fungal metabolic products reduced 50% and 70% of the spermatozoa motility after 2 and 24 hours culture with spermatozoa, respectively. Clinical implications and impact of asymptomatic candidiasis on fertility will be discussed.