Research
Hormonal
There is a significant inverse association between the increasing number of nights worked in the 2 weeks preceding urine collection and urinary melatonin levels (r = −0.30, P = 0.008).
Practitioners should consider that recent night work may reduce melatonin levels in women.
GoodSupportsmedium confidence
We observed a significant inverse association between increasing number of nights worked within the 2 weeks preceding urine collection and urinary melatonin levels (r = −0.30, P = 0.008).
Why this rating
Based on the analysis of data from a cohort study.
Source
Epidemiology of Urinary Melatonin in Women and Its Relation to Other Hormones and Night Work
Eva Schernhammer et al. · Cancer Epidemiology Biomarkers & Prevention · 2004
DOI 10.1158/1055-9965.936.13.6
cohort · n=80Cited 215×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
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