Clinical Outcomes of In Vitro Fertilization among Chinese Infertile Couples Treated for Syphilis Infection

The impact of HBV, HCV, or syphilis infections on embryo and pregnancy outcomes in couples undergoing IVF treatment: a matched cohort study

STUDY QUESTION

Do infectious diseases (hepatitis B virus [HBV], hepatitis C virus [HCV], and syphilis) impact embryo quality, pregnancy, and neonatal outcomes following a complete IVF cycle?

SUMMARY ANSWER

Infections with HBV, HCV, or syphilis do not have detrimental impacts on live birth rates or neonatal outcomes in couples following a complete IVF cycle.

WHAT IS KNOWN ALREADY

Maternal or paternal infections with HBV, HCV, or syphilis may decrease the clinical pregnancy rate, result in poorer embryo outcomes, and lower offspring birth weight. However, there is significant controversy regarding these effects across existing studies, highlighting the need for further research.

STUDY DESIGN SIZE DURATION

This is a retrospective matched cohort study. Data were obtained from the clinical database of couples who underwent IVF treatment at a single academically affiliated fertility clinic from January 2011 to December 2019, with follow-up extending to December 2020. Out of 180 666 complete cycles recorded, 2443 cycles fulfilled our inclusion criteria.

PARTICIPANTS/MATERIALS SETTING METHODS

In cycles that fulfilled our inclusion criteria, there were 1997 cycles in the HBV study group, 154 cycles in the HCV study group, and 292 cycles in the syphilis study group. Each study cycle was paired with four controls based on participant age and the timing of IVF treatment, resulting in 7988 controls for the HBV group, 616 controls for the HCV group, and 1169 controls for the syphilis group. Infections could be either single-parent or biparental. The primary outcome was live birth per complete cycle (i.e. fresh cycle plus subsequent frozen-thawed cycles). Subgroup analyses were conducted dividing cycles into maternal infection and paternal infection.

MAIN RESULTS AND THE ROLE OF CHANCE

In the HBV group, pregnancy outcomes (clinical pregnancy, miscarriage, and live birth rates) and neonatal birth weight were similar to that of the controls. In the HCV group, no significant differences from the controls were observed except for a lower clinical pregnancy rate in the study group (36.4% vs 42.2%, adjusted β and 95% CI: 0.62 [0.39-0.96]). Similarly, no significant differences were found in pregnancy or neonatal outcomes between the syphilis group and the control group. As for subgroup analyses, the male-only HBV infection subgroup showed a higher miscarriage rate in the study group than in the control group (22.5% vs 17.7%, adjusted β and 95% CI: 1.56 [1.07-2.28]). For the HCV and syphilis subgroups, none of the outcomes showed significant differences between either the female-only infection or male-only infection subgroups and the controls.

LIMITATIONS REASONS FOR CAUTION

Although potential confounders were considered and adjusted for, residual bias may still exist due to the study design. The inclusion of participants solely from a single center limited the generalizability of our findings to a broader context.

WIDER IMPLICATIONS OF THE FINDINGS

We presented a comprehensive overview of the impact of prevalent infectious diseases on IVF outcomes, hoping to address uncertainties surrounding the decisions of couples infected with these diseases and to assist in preventing adverse reproductive outcomes in clinical practice.

STUDY FUNDING/COMPETING INTERESTS

This study was supported by the National Natural Science Foundation of China (82204052), the National Key R&D Program of China (2022YFC2705305), and the Clinical key project of Peking University Third Hospital (BYSYZD2023007). The authors declare no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Study on the influence of syphilis on the outcome of frozen-thawed embryo transfer in infertility patients

Objective

In this study, the effect of in vitro Fertilization-Embryo Transfer (IVF-ET) on the clinical outcome of patients with syphilis infertility during resuscitation cycle.

Methods

A retrospective single-center method was adopted. This study included 4430 pairs of infertile patients who underwent syphilis detection. The influence of the syphilis freeze-thaw embryos transplantation outcome was studied in the patients with infertility by comparing the general clinical characteristics of patients (age, years of infertility, body mass index (BMI), basal follicle stimulating hormone (FSH), serum basal estradiol (Estradiol, E2), transplanted intimal thickness, the number of embryos transferred) and the clinical pregnancy (biochemical pregnancy rate, clinical pregnancy rate, implantation rate, live birth rate and abortion rate).

Results

Firstly, in the clinical outcome of one frozen-thawed embryos transfer, the live birth rate of the woman's syphilis-infected group was lower than that of the uninfected group (71.3 % vs. 50.0 %), while the abortion rate was higher than that of the uninfected group (7.8 % vs. 26.7 %), and there was a statistical difference (P < 0.05), and there was no statistical difference in other indicators between other groups (P > 0.05). Secondly, in the clinical outcome of two frozen-thawed embryos transfers, the biochemical pregnancy rate (61.3 % vs. 28.6 %) and clinical pregnancy rate (42.9 % vs. 14.3 %) of the group which was infected with syphilis alone were lower than those of the uninfected group (P < 0.05), and other indicators among the other groups showed no statistical difference (P > 0.05). Thirdly, in the clinical outcomes of frozen-thawed embryos transfer three times or more, there was no significant difference in the clinical indicators between the syphilis infertility patients and the non-infected infertility patients (P > 0.05).

Conclusion

When the syphilis infertility patients and the non-infected infertile patients underwent IVF-ET treatment for the first time, the live birth rate and abortion rate of the syphilis group were significantly different (P < 0.05). In the outcome of two transplants, the biochemical pregnancy rate and clinical Pregnancy rates were significantly reduced so patients with syphilis infertility who undergo IVF-ET should be informed about the risk of adverse clinical outcomes.

The negative impact of most relevant infections on fertility and assisted reproduction technology

Infections may act with variable impact on the physiopathology of the reproductive organs, determining infertility or reducing the outcomes of assisted reproduction technology. The aim of this narrative review is to describe the existing evidence regarding the pathogens with a supposed or recognized role in reproductive medicine. Viral hepatitis, as well as HIV, can reduce sperm quality. Syphilis carries a risk of erectile dysfunction and increased endometrial thickness. Chlamydia is the main cause of pelvic inflammatory disease. In relation to Mycoplasma and Ureaplasma spp., only few species seem to show a correlation with infertility and poor in-vitro fertilization outcomes. There is evidence of a role for bacterial vaginosis in early pregnancy loss. HPV infection in males seems to determine infertility. Herpesviruses are more a risk for fetuses than for fertility itself. Zika virus is responsible for altered early embryo development and waiting to conceive is recommended in suspected or confirmed cases. The impact of SARS-CoV-2 is yet to be elucidated. Rubella and toxoplasmosis can provoke important congenital defects and therefore screening is mandatory before conception; a vaccine for Rubella is recommended. Further and well-designed studies are still needed to better elucidate the role of some infectious agents, to improve fertility and its treatments.

Presence of Chlamydia trachomatis and Mycoplasma spp., but not Neisseria gonorrhoeae and Treponema pallidum, in women undergoing an infertility evaluation: high prevalence of tetracycline resistance gene tet(M)

Chlamydia trachomatis, Mycoplasma spp., Neisseria gonorrhoeae and Treponema pallidum are sexually transmitted pathogens that threaten reproductive health worldwide. In this study, vaginal swabs obtained from women (n = 133) that attended an infertility clinic in China were tested with qPCRs for C. trachomatis, Mycoplasma spp., N. gonorrhoeae, T. pallidum and tetracycline resistance genes. While none of vaginal swabs were positive for N. gonorrhoeae and T. pallidum, 18.8% (25/133) of the swabs were positive for Chlamydia spp. and 17.3% of the swabs (23/133) were positive for Mycoplasma species. All swabs tested were positive for tetracycline resistance gene tet(M) which is the most effective antibiotic for bacterial sexually transmitted infections. The qPCRs determined that the gene copy number per swab for tet(M) was 7.6 times as high as that of C. trachomatis 23S rRNA, and 14.7 times of Mycoplasma spp. 16S rRNA. In China, most hospitals do not detect C. trachomatis and Mycoplasma spp. in women with sexually transmitted infections and fertility problems. This study strongly suggests that C. trachomatis and Mycoplasma spp. should be routinely tested in women with sexually transmitted infections and infertility in China, and that antimicrobial resistance of these organisms should be monitored. Further studies are warranted to determine the prevalences in different regions and associated risk factors.