Lactobacillus crispatus-dominated vaginal microbiome and Acinetobacter-dominated seminal microbiome support beneficial ART outcome

INTRODUCTION

Despite the considerable progress made in assisted reproductive technologies (ART), the implantation rate of transferred embryos remains low and in many cases, the reasons for failure remain unclear. We aimed to determine the potential impact of female and male partners' reproductive tract microbiome composition on ART outcome.

MATERIAL AND METHODS

The ART couples (n = 97) and healthy couples (n = 12) were recruited into the study. The smaller healthy group underwent a careful selection according to their reproductive and general health criteria. Both vaginal and semen samples were subjected to 16S rDNA sequencing to reveal the bacterial diversity and identify distinct microbial community types. Ethics statement The study was approved by the Ethics Review Committee on Human Research of Tartu University, Tartu, Estonia (protocol no. 193/T-16) on 31 May 2010. Participation in the research was voluntary. Written informed consent was obtained from all study participants.

RESULTS

The men with Acinetobacter-associated community who had children in the past, had the highest ART success rate (P < 0.05). The women with bacterial vaginosis vaginal microbiome community and with L. iners-predominant and L. gasseri-predominant microbiome had a lower ART success rate than women with the L. crispatus-predominant or the mixed lactic-acid-bacteria-predominant type (P < 0.05). The 15 couples where both partners had beneficial microbiome types had a superior ART success rate of 53%, when compared with the rest of the couples (25%; P = 0.023).

CONCLUSIONS

Microbiome disturbances in the genital tract of both partners tend to be associated with couple's infertility as well as lower ART success levels and may thus need attention before the ART procedure. The incorporation of genitourinary microbial screening as a part of the diagnostic evaluation process may become routine for ART patients if our results are confirmed by other studies.

VNTR I/I genotype of insulin gene is associated with the increase of follicle number independent from polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is accompanied by selective insulin resistance and enhanced ovarian steroidogenic effects of insulin. We analysed the minisatellite variations of the insulin gene (INS VNTR) with regard to the clinical features of PCOS.

METHODS

Retrospective, adjusted association study. Infertile patients with PCOS (n=30) and tubal factor (n=75) were screened for anthropometrical, clinical and ovarian morphology parameters, as well as hormonal values. INS VNTR was genotyped by its surrogate marker at -23 HphI locus.

RESULTS

INS VNTR genotype distribution was similar in PCOS and tubal infertility group. The mean ovarian follicle number was higher in VNTR I/I individuals compared to VNTR I/III and III/III individuals (adjusted OR=1.28, p=0.03), independent from the cause of infertility, the age, the follicle stimulating hormone level on day 3-5 of menstrual cycle, BMI and the previous surgical ovarian tissue removal. In addition, higher level of the luteinising hormone in VNTR I/I individuals was associated with the increase in follicle number.

CONCLUSIONS

We suggest that INS VNTR genotypes are not associated with PCOS in general, but could have a certain influence on the phenotypic spectrum of the syndrome.