Associations of parabens and age at natural menopause: National Health and Nutrition Examination Survey

Abstract

Abstract Background: Parabens were considered to have potential negative impacts on reproductive health. This study aimed to examine the association between parabens and the onset of natural menopause. Methods: This cross-sectional study included 2,668 participants from National Health and Nutrition Examination Survey 2005-2016. The outcome of this study was the onset of menopause. The exposure of this study was four parabens, including butyl paraben (BP), ethyl paraben (EP), methyl paraben (MP), and propyl paraben (PP). Each paraben was categorized based on its tertile. Weighted COX regression models were employed to investigate the associations between BP, EP, MP, PP, and onset of natural menopause, respectively. Subgroup analyses were conducted based on smoke status, drink status, and oral contraceptives. Results: Natural menopause occurred in 1043 women in the total population. Compared with women with the lowest tertile of EP, women in the second tertile of EP [hazard ratio (HR) = 1.26, 95% confidence interval (CI): 1.01-1.57] and the highest tertile of EP (HR = 1.28, 95% CI: 1.01-1.64) was associated with an increased risk of earlier onset of naturalmenopause. However, all BP, MP, and PP levels were not statistically associated with the onset of naturalmenopause. The results of subgroup analysis indicated that EP, MP, and PP were all associated with the earlier onset of natural menopause in women who did not used oral contraceptives. Conclusion:Our findings suggested an association between higher EP levels and an earlier onset of natural menopause in general U.S. women. The findings of our study necessitate further prospective epidemiologic research to validate.