Microbiome and Metabolome Profiles in Couples Undergoing IVF and Reproductive Outcomes

Microbiome and Metabolome Profiles in Couples Undergoing IVF and Their Association With Reproductive Outcomes in a Prospective Longitudinal Cohort Study

This prospective observational cohort study investigates the role of the microbiome and metabolome in couples undergoing in vitro fertilization. Biological samples will be collected from both female and male partners, including semen, vaginal, and blood samples, to characterize microbial composition and metabolic profiles. The study aims to examine how these biological profiles are associated with reproductive outcomes such as fertilization, pregnancy, miscarriage, and live birth. Participants will be followed longitudinally, and reproductive and obstetric outcomes will be obtained through linkage with national health registers.

Infertility affects a substantial proportion of couples worldwide, and in vitro fertilization (IVF) is an important treatment option for many individuals experiencing infertility. Increasing evidence suggests that the human microbiome and metabolome may play a role in reproductive health and fertility outcomes. However, the contribution of microbial communities and metabolic profiles in both female and male partners to IVF outcomes remains insufficiently understood.

This prospective observational cohort study aims to investigate the microbiome and metabolome profiles in couples undergoing IVF treatment and their association with reproductive and obstetric outcomes. Heterosexual couples undergoing IVF treatment at participating fertility clinics will be recruited. Biological samples will be collected from both partners, including semen samples from male partners and vaginal and blood samples from female partners. These samples will be stored and analyzed using sequencing-based microbiome profiling and metabolomic analyses.

The study will evaluate microbial composition, diversity, and metabolic signatures in relation to fertility parameters such as semen quality, fertilization rate, embryo development, and clinical pregnancy. Participants will be followed longitudinally to assess reproductive outcomes including miscarriage, preterm birth, preeclampsia, and live birth. Outcome data will be obtained through clinical records and linkage with national health registers.

The overall aim of the study is to improve the understanding of how microbiome and metabolome profiles in both partners may influence reproductive success and pregnancy outcomes in couples undergoing IVF.

Inclusion Criteria:

• Women aged 18 to 40 years at enrolment.
• Men aged between 18 to 56 years at enrolment.
• Couples planning to undergo IVF treatment at a participating centre.
• Sufficient understanding of spoken and written Swedish or English to provide informed consent and complete the web-based questionnaire.

Exclusion Criteria:

• Pregnancy at the time of enrolment (confirmed or suspected).
• Recent systemic antibiotic use within the past 4 weeks
• Active vaginal or genital tract infection at the time of sampling