Association of serum levels of typical organic pollutants with polycystic ovary syndrome (PCOS): a case-control study.
STUDY QUESTION
Is polycystic ovary syndrome (PCOS) associated with increased serum levels of typical organic pollutants?


SUMMARY ANSWER
PCOS in Han females from Northern China was significantly associated with elevated serum levels of pollutants, including polychlorinated biphenyls (PCBs), organochlorine pesticides and polycyclic aromatic hydrocarbons (PAHs).


WHAT IS KNOWN ALREADY
PCOS is arguably the most common endocrinopathy in females of reproductive age. The etiology of PCOS is thought to be multifactorial.


STUDY DESIGN, SIZE, DURATION
This was a preliminary case-control study undertaken at the Division of Reproductive Center, Peking University Third Hospital. Fifty participants affected by PCOS and 30 normal controls were recruited between August and October 2012 from Northern China. All participants were Han women.


PARTICIPANTS/MATERIALS, SETTING, METHODS
PCOS participants were diagnosed according to the 2003 Rotterdam criteria. The control participants were non-pregnant females unable to conceive solely due to male azoospermia. Serum levels of a wide range of organic pollutants, including PCBs, organochlorine pesticides, PAHs and more than 20 phenolic pollutants, were analyzed using gas chromatographic mass spectrometry.


MAIN RESULTS AND THE ROLE OF CHANCE
Serum levels of PCBs, pesticides and PAHs were significantly higher in the PCOS group than the control group. Concentrations of PCBs, p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) and PAHs in serum above median levels were associated with PCOS with odds ratios of 3.81 [95% confidence interval (CI), 1.45-10.0], 4.89 (95% CI, 1.81-13.2) and 2.39 (95% CI, 0.94-6.05), respectively. Partial least-squares-discriminant analysis (PLS-DA) confirmed that serum levels of organic pollutants were associated with PCOS, especially for p,p'-DDE and PCBs.


LIMITATIONS, REASONS FOR CAUTION
Some other possible covariates (e.g. dietary and income) were missed in this study, although education and occupation have been considered as an indicator of personal income. The PLS-DA model allowed a quasi-exposome analysis with over 60 kinds of typical organic pollutants; however, the possibility of other pollutants involved in the PCOS still could not be excluded.


WIDER IMPLICATIONS OF THE FINDINGS
Our study identified that bodily retention of environmental organic pollutants-including PCBs, pesticides (especially p,p'-DDE) and PAHs-was associated with PCOS.


STUDY FUNDING/COMPETING INTERESTS
This research was supported by the Ministry of Science and Technology of China Grants (973 program; 2014CB943203 and 2015CB553401), National Natural Science Foundation of China (21322705, 21190051, 41121004 and 81170538), National Key Technology R&D Program in the Twelve Five-Year Plan (2012BAI32B01) and the Collaborative Innovation Center for Regional Environmental Quality. There are no conflicts of interest to declare.


TRIAL REGISTRATION NUMBER
None. This is not a clinical trial.
['Yang|Qiaoyun|Q|', 'Zhao|Yue|Y|', 'Qiu|Xinghua|X|', 'Zhang|Chunmei|C|', 'Li|Rong|R|', 'Qiao|Jie|J|']
D000328:Adult D016022:Case-Control Studies D002681:China D004785:Environmental Pollutants D005260:Female D006801:Humans D006843:Hydrocarbons, Chlorinated D010575:Pesticides D011078:Polychlorinated Biphenyls D011085:Polycystic Ovary Syndrome
polycystic ovary syndrome (PCOS) partial least-squares-discriminant analysis (PLS-DA) case–control study endocrine-disrupting chemicals (EDCs) persistent organic pollutants (POPs)