title: Prolonged menstrual cycles in female workers exposed to ethylene glycol ethers in the semiconductor manufacturing industry.
abstract: BACKGROUND
  It has been shown that female workers exposed to ethylene glycol ethers (EGEs) in the semiconductor industry have higher risks of spontaneous abortion, subfertility, and menstrual disturbances, and prolonged waiting time to pregnancy.
  
  
  OBJECTIVE
  To examine whether EGEs or other chemicals are associated with long menstrual cycles in female workers in the semiconductor manufacturing industry.
  
  
  METHODS
  Cross-sectional questionnaire survey during the annual health examination at a wafer manufacturing company in Taiwan in 1997. A three tiered exposure-assessment strategy was used to analyse the risk. A short menstrual cycle was defined to be a cycle less than 24 days and a long cycle to be more than 35 days.
  
  
  RESULTS
  There were 606 valid questionnaires from 473 workers in fabrication jobs and 133 in non-fabrication areas. Long menstrual cycles were associated with workers in fabrication areas compared to those in non-fabrication areas. Using workers in non-fabrication areas as referents, workers in photolithography and diffusion areas had higher risks for long menstrual cycles. Workers exposed to EGEs and isopropanol, and hydrofluoric acid, isopropanol, and phosphorous compounds also showed increased risks of a long menstrual cycle.
  
  
  CONCLUSIONS
  Exposure to multiple chemicals, including EGEs in photolithography, might be associated with long menstrual cycles, and may play an important role in a prolonged time to pregnancy in the wafer manufacturing industry; however, the prevalence in the design, possible exposure misclassification, and chance should be considered.
authors.affiliation: Institute of Occupational Medicine and Industrial Hygiene, National Taiwan University College of Public Health, 1, Section 1, Jen-Ai Road, Taipei 100, Taiwan.
authors.forename: G-Y
authors.initials: GY
authors.lastname: Hsieh
authors.forename: J-D
authors.initials: JD
authors.lastname: Wang
authors.forename: T-J
authors.initials: TJ
authors.lastname: Cheng
authors.forename: P-C
authors.initials: PC
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000328:Adult; D016009:Chi-Square Distribution; D003430:Cross-Sectional Studies; D005026:Ethylene Glycols / Q000633:toxicity*; D005260:Female; D006801:Humans; D008420:Manufactured Materials / Q000009:adverse effects; D008597:Menstrual Cycle / Q000187:drug effects*; D008599:Menstruation Disturbances / Q000139:chemically induced*; D009784:Occupational Diseases / Q000139:chemically induced*; D016273:Occupational Exposure / Q000009:adverse effects*; D012666:Semiconductors; D011795:Surveys and Questionnaires; D013624:Taiwan
chemical_list: D005026:Ethylene Glycols