Grindler, N. M., Allsworth, J. E., Macones, G. A., Kannan, K., Roehl, K. A., & Cooper, A. R. (2015). Persistent organic pollutants and early menopause in U.S. women. PloS one. https://doi.org/10.1371/journal.pone.0116057
Grindler NM, Allsworth JE, Macones GA, Kannan K, Roehl KA, Cooper AR. Persistent organic pollutants and early menopause in U.S. women. PloS one. 2015. doi:10.1371/journal.pone.0116057
Grindler, N. M., et al. "Persistent organic pollutants and early menopause in U.S. women." PloS one, 2015.
Higher levels of 15 chemicals link to earlier menopause in US women
In a national survey of 1,442 US women past menopause, women with high levels of 15 chemicals went through menopause 1.9 to 3.8 years earlier. The chemicals were nine PCBs, three pesticides, one furan and two phthalates, measured in blood or urine between 1999 and 2008.
Key Findings
Of 111 chemicals, the authors focused on 35 with long half-lives and phthalates. Fifteen were significantly associated with menopause 1.9 to 3.8 years earlier on average in women with high levels.
The 15 chemicals were nine PCBs, three pesticides (β-hexachlorocyclohexane, mirex and p,p’-DDE), a furan and two phthalates.
Nine of the 10 chemicals significantly associated with earlier menopause in the threshold analysis were also significant in one of the two dose-response analyses.
In women aged 45 to 55 years, the odds ratio for being menopausal was 6.59 (95% CI 2.31 to 18.9) per unit of log PCB-183 and 6.31 (2.68 to 14.8) for PCB-105.
The authors report that differences of 1.9 to 3.8 years exceed the 0.8 to 1.4 years of earlier menopause that prior NHANES studies associated with tobacco smoke.
Interpretation
The study is a cross-sectional analysis of NHANES, a national survey run by the CDC. Chemical levels were measured once. Women who had gone 12 months without a period recalled their age at the last menstrual period. The sample excluded women who were pregnant, breastfeeding or using hormonal contraception, and women with a hysterectomy or bilateral oophorectomy. Models adjusted for age, race, body mass index and smoking. The authors call the findings hypothesis-generating and ask for animal models and prospective studies.
RRM Context
RRM looks for the cause behind early loss of ovarian function, and an exposure history fits that approach. The paper's introduction says endocrine-disrupting chemicals as a class have been linked to reduced sperm quality, lower fecundity and more pregnancy complications. The exposure question applies to both partners.
Our editorial summary of this paper, not the article's abstract.
Abstract
Objective
Endocrine-disrupting chemicals (EDCs) adversely affect human health. Our objective was to determine the association of EDC exposure with earlier age of menopause.
Methods
Cross-sectional survey using National Health and Nutrition Examination Survey (NHANES) data from 1999 to 2008 (n = 31,575 females). Eligible participants included: menopausal women >30 years of age; not currently pregnant, breastfeeding, using hormonal contraception; no history of bilateral oophorectomy or hysterectomy. Exposures, defined by serum lipid and urine creatinine-adjusted measures of EDCs, data were analyzed: > 90th percentile of the EDC distribution among all women, log-transformed EDC level, and decile of EDC level. Multi linear regression models considered complex survey design characteristics and adjusted for age, race/ethnicity, smoking, body mass index. EDCs were stratified into long (>1 year), short, and unknown half-lives; principle analyses were performed on those with long half-lives as well as phthalates, known reproductive toxicants. Secondary analysis determined whether the odds of being menopausal increased with EDC exposure among women aged 45-55 years.
Findings
This analysis examined 111 EDCs and focused on known reproductive toxicants or chemicals with half-lives >1 year. Women with high levels of β-hexachlorocyclohexane, mirex, p,p'-DDE, 1,2,3,4,6,7,8-heptachlorodibenzofuran, mono-(2-ethyl-5-hydroxyhexyl) and mono-(2-ethyl-5-oxohexyl) phthalate, polychlorinated biphenyl congeners -70, -99, -105, -118, -138, -153, -156, -170, and -183 had mean ages of menopause 1.9 to 3.8 years earlier than women with lower levels of these chemicals. EDC-exposed women were up to 6 times more likely to be menopausal than non-exposed women.
Conclusions
This study of a representative sample of US women documents an association between EDCs and earlier age at menopause. We identified 15 EDCs that warrant closer evaluation because of their persistence and potential detrimental effects on ovarian function. Earlier menopause can alter the quantity and quality of a woman's life and has profound implications for fertility, human reproduction, and our global society.
