Cohort study, 2019
Does insomnia from shift work cause irregular periods?
Yes. Nurses with insomnia had 2-3 times higher odds of developing irregular periods compared to those without insomnia. The more severe the insomnia, the higher the risk.
What they did
A prospective cohort study of 287 newly-employed nurses followed for 12 months from 2015-2016. At 6 months, insomnia was measured using the Insomnia Severity Index (ISI). Menstrual cycle information was collected at the start and at 12 months through clinical interviews.
What they found
Nurses with insomnia had 2.05-fold higher odds of newly developing menstrual cycle irregularity (95% CI 1.12-3.77) compared with nurses without insomnia. Nurses with insomnia had 3.05-fold higher prevalence of menstrual cycle irregularity (95% CI 1.81-5.13). As insomnia severity increased, both the odds of developing and having irregular periods increased.
What it means for you
Insomnia from shift work may directly cause menstrual irregularity, separately from effects of disrupted sleep-wake cycles. This suggests sleep quality itself matters for period regularity. However, the study only looked at nurses, so results may not apply to other jobs or populations.
287
Total nurses enrolled
2.05
Fold increase in odds of new irregularity
3.05
Fold increase in irregularity prevalence
About the study
- Original title
- The menstrual cycle associated with insomnia in newly employed nurses performing shift work: a 12-month follow-up study
- Authors
- Kang W, Jang KH, Lim HM et al.
- Journal
- International archives of occupational and environmental health
- Year
- 2019
- Study design
- Cohort study
- Participants
- 287
- Read the paper
- doi.org/10.1007/s00420-018-1371-y
Topics
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