World Health Organization grade ‘a’ motility and zona-binding test accurately predict IVF outcome for mild male factor and unexplained infertilities

BACKGROUND: The aim of this study was to determine the pronostic value of a sperm–zona pellucida (ZP) binding assay, combined with World Health Organization (WHO) grade ‘a’ sperm motility on the day of the IVF attempt, to predict sperm fertilizing ability in unexplained and moderate male factor infertilities. METHODS: In total, 84 couples (64 unexplained infertility; 20 male factor) underwent both a sperm–ZP binding assay and an IVF attempt, irrespective of the test’s result. The test was negative when grade ‘a’ motility was #5% and/or the ZP binding index was