A Core Outcome Set for Future Male Infertility Research: Development of an International Consensus.

Rimmer MP, Howie RA, Anderson RA, et al.

Hum Reprod. 2025 May 1;40(5):865-875. doi: 10.1093/humrep/deaf039. PMID: 40233940; PMCID: PMC12046074.

Study Question: Can a global consensus develop a COS for male infertility trials?

Manuscript Overview

The manuscript describes the development of a standardized core outcome set (COS) for male infertility research, specifically for use in randomized controlled trials (RCTs) and systematic reviews to improve consistency and clinical utility.

Methodology

The study used a two-round Delphi survey involving 334 participants from 39 countries, followed by consensus workshops with 44 participants from 21 countries. Participants included healthcare professionals, researchers, and individuals with lived experience of infertility.

Core Outcome Set (COS) Components

The resulting COS includes:

• General Infertility Outcomes: Viable intrauterine pregnancy confirmed by ultrasound (including singleton and multiple pregnancies), pregnancy loss (ectopic pregnancy, miscarriage, stillbirth, and termination), live birth, gestational age at delivery, birthweight, neonatal mortality, and major congenital anomaly.
• Male-Specific Outcome: Semen analysis using World Health Organization (WHO) recommendations.
• Additional outcomes may be considered in specific research contexts but are not mandatory.

Purpose of the COS

The aim of this COS is to address the significant heterogeneity and selective reporting in male infertility trials, which has historically limited the comparability and clinical utility of research findings.

Support and Adoption

The adoption of this COS is supported by major research funding bodies, the SPIRIT statement, and over 80 specialty journals, including Cochrane Gynaecology and Fertility Group, Fertility and Sterility, and Human Reproduction, to improve consistency and transparency in outcome reporting for male infertility research.