Serum oestradiol levels in male partners of infertile couples

A prospective clinical study was performed in the reproduction centre of Ichikawa General Hospital (Chiba, Japan) to investigate the relationship between sperm quality and serum oestradiol (E2) level in male partners of infertile couples. The semen parameters and blood samples were assessed in relation to several variables, including body mass index (BMI) and serum oestradiol (E2) levels. Four hundred and nine male partners of infertile couples aged 22–55 years (mean: 36.5 years) were referred to the reproduction centre. In total, 143 patients (35.0%) were included in the low E2 level group (18 pg ml^?1 ≥ E2). Serum E2 levels were slightly correlated with testosterone levels, BMI and serum FSH levels. Total motile sperm count and morphology were decreased in low E2 level group. In multivariate analysis, serum testosterone, E2 levels, existence of varicocele and age were risk factors for decreased semen quality. Serum E2 might be associated with BMI, serum testosterone level and spermatogenesis.