Research
Hormonal
Women who worked 15 or more years of night shifts had a geometric mean level of estradiol of 10.1 pg/mL compared to 8.8 pg/mL for women who never worked night shifts (P for trend = 0.03).
Practitioners should be aware that long-term night shift work may influence estradiol levels in women.
GoodSupportsmedium confidence
We found significantly increased levels of estradiol after longer durations of night work (geometric mean levels of estradiol, 8.8 pg/mL for women who never worked night shifts versus 10.1 pg/mL for women who worked 15 or more years of night shifts; P for trend = 0.03).
Why this rating
Based on the use of data from two large, prospective cohorts.
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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