Andrological impairment of variable extent was found in 26 of 141 partners, and 80 (35.1 %) of the female patients reported on abnormal findings: tubal incompetence (extrauterine pregnancy ×6, unilaterial salpingectomy ×4, adhesions ×3), uterine (myoma ×4, septate uterus ×5, polyp ×1, conisation for cervical dysplasia ×4), endometriosis (n = 5), thyroid disease (Hashimoto thyroiditis, struma, n = 11), endocrine (corpus luteum incompetence, polycystic ovary syndrome, hyperandrogenaemia, hyperprolactinaemia, n = 28), factor V Leiden mutation (n = 9). The gene discussed is F5; the disease is Increased circulating prolactin concentration.