Rotating Shift Work and Menstrual Cycle Characteristics

Details

• Alternative Title:
  Epidemiology
• Personal Author:
  Lawson, Christina C. ; Whelan, Elizabeth A. ; Lividoti Hibert, Eileen N. ; Spiegelman, Donna ; Schernhammer, Eva S. ; Rich-Edwards, Janet W.
• Description:
  Background
  
  Shift workers who experience sleep disturbances and exposure to light at night could be at increased risk for alterations in physiologic functions that are circadian in nature.
  
  Methods
  
  We investigated rotating shift work and menstrual cycle patterns in the Nurses’ Health Study II using cross-sectional data collected in 1993 from 71,077 nurses aged 28–45 years who were having menstrual periods and were not using oral contraceptives. Log binomial regression was used to estimate relative risks (RRs) and 95% confidence intervals (CIs).
  
  Results
  
  Eight percent of participants reported working rotating night shifts for 1–9 months, 4% for 10–19 months, and 7% for 20+ months during the previous two years. Irregular cycles (>7 days variability) were reported by 10% of participants. Seventy percent of women reported menstrual cycles of 26–31 days, 1% less than 21 days, 16% 21–25 days, 11% 32–39 days, and 1% 40+ days. Women with 20+ months of rotating shift work were more likely to have irregular cycles (adjusted RR = 1.23 CI = 1.14–1.33); They were also more likely to have cycle length <21 days (1.27 0.99–1.62) or 40+ days (1.49 1.19–1.87) (both compared with 26–31 days). For irregular patterns and for 40+ day cycles, there was evidence of a dose response with increasing months of rotating shift work. Moderately short (21–25 days) or long (32–39 days) cycle lengths were not associated with rotating shift work.
  
  Conclusion
  
  Shift work was modestly associated with menstrual function, with possible implications for fertility and other cycle-related aspects of women’s health.
• Subjects:
  • Adaptation, Physiological
  • Adult
  • Age Factors
  • Chronobiology Disorders
  • Confidence Intervals
  • Cross-Sectional Studies
  • Female
  • Humans
  • Incidence
  • Linear Models
  More +
• Source:
  Epidemiology. 22(3):305-312.
• Pubmed ID:
  21364464
• Pubmed Central ID:
  PMC5303197
• Document Type:
  Journal Article
• Funding:
  R01 OH009803/OH/NIOSH CDC HHS/United States ; 200-2001-08007/PHS HHS/United States
• Volume:
  22
• Issue:
  3
• Download URL:
  https://stacks.cdc.gov/view/cdc/44155/cdc_44155_DS1.pdf
• File Type:
  [PDF - 124.10 KB]
• Collection(s):
  CDC Public Access
• Main Document Checksum:
  urn:sha-512:d0b5e4b83e2173509944967ac1e1909cc587335aa8f2fa0f235b38f8481f966d015037377ccff472101a66166dc21d2d0eb0bc3b1a40ae6c488cf021f8e19be5