背景:不孕症影响了16%的北美夫妇,男性因素不育症占病例的30%。生殖激素,尤其是睾丸激素,对精子发生至关重要。在过去的几十年中,睾酮浓度的年龄独立于人群水平的下降被认为是饮食和生活方式改变的结果。维生素B12存在于睾丸中,由于其改善精子参数的潜力,已被建议作为男性不育的辅助营养疗法。然而,研究维生素B12和生殖激素之间关系的证据是有限的。
目的:目的是对血清维生素B12与男性生殖激素(黄体生成素,卵泡刺激素,总睾酮,雌二醇和催乳素)。
方法:从多伦多的西奈山医院招募患有不孕症的男性(n=303),加拿大。分析血清中的维生素B12和生殖激素。统计分析包括非参数斯皮尔曼秩相关系数,线性回归,年龄和BMI线性回归的逻辑回归和效应修正。
结果:观察到血清维生素B12与总睾酮之间的独立单调关系(rho=0.19,P=0.001)。血清维生素B12与总睾酮呈线性相关(未调整β=0.0007,P=0.008,调整β=0.0005,P=0.03)。与血清维生素B12最低三分位数的个体相比,中间三分位数的个体(调整后的OR=0.48,95%CI[0.25,0.93],P=0.03)和最高三分位数(未调整OR=0.41,95%CI[0.22,0.77],P=0.005,调整后的OR=0.44,95%CI[0.22,0.87],P=0.02)降低了睾酮缺乏的几率。
结论:这些研究结果表明,在男性不孕症患者中,低血清维生素B12与睾酮缺乏和影响精子发生的雄激素激素谱受损的较高风险相关,生育率。
BACKGROUND: Infertility impacts 16% of North American couples, with male factor
infertility contributing to ∼30% of cases. Reproductive hormones, especially testosterone, are essential for spermatogenesis. Age-independent population-level decline in testosterone concentrations over the past few decades has been proposed to be a result of diet and lifestyle changes. Vitamin B12 is present in the testes and has been suggested as an adjuvant nutritional therapy for male
infertility due to its potential to improve sperm parameters. However, evidence examining the relationship between vitamin B12 and reproductive hormones is limited.
OBJECTIVE: The objective was to cross-sectionally examine the relationship between serum vitamin B12 and male reproductive hormones (luteinizing hormone, follicular stimulating hormone, total testosterone, estradiol and prolactin).
METHODS: Men with
infertility (n = 303) were recruited from Mount Sinai Hospital in Toronto, Canada. Serum was analyzed for vitamin B12 and reproductive hormones. Statistical analyses included non-parametric Spearman\'s rank correlation coefficient, linear regression, logistic regression and effect modification by age and BMI linear regressions.
RESULTS: An independent monotonic relationship between serum vitamin B12 and total testosterone (rho = 0.19, P = 0.001) was observed. Serum vitamin B12 was linearly associated with total testosterone (unadjusted ß = 0.0007, P = 0.008 and adjusted ß = 0.0005, P = 0.03). Compared to individuals in the lowest tertile of serum vitamin B12, those in the middle tertile (adjusted OR = 0.48, 95% CI [0.25, 0.93], P = 0.03) and the highest tertile (unadjusted OR = 0.41, 95% CI [0.22, 0.77], P = 0.005 and adjusted OR = 0.44, 95% CI [0.22, 0.87], P = 0.02) had reduced odds of testosterone deficiency.
CONCLUSIONS: These findings suggest that among men with
infertility, low serum vitamin B12 is associated with higher risk of testosterone deficiency and impaired androgenic hormonal profiles that impact spermatogenesis and consequently, fertility.