Table 1.

Main characteristics of included studies on the relationship between night shift work and the risks of common cancers in female populations

StudyPublished yearNo. of cases/No. of subjectsOR (95% CI)Study designQuality scoreRegionType of cancerRange of night shift workOccupationVariables of adjustmentExposure assessment method
Knutsson A201294/4,0362.02 (1.03–3.95)Cohort study7SwedenBreast cancerDay vs. night shiftNANumber of children, alcohol consumption, BMI, height, weight, waist, hip circumference, educational level, smoking menopausal status, status of oral contraceptive use, and hormones other than contraceptivesQuestionnaire
Carter BD20141,289/16,10041.27 (1.03–1.56)Cohort study8USAOvarian cancerDay vs. rotating shiftsNAOral contraceptive use, age at menarche and menopause, tubal ligation, parity, postmenopausal estrogen use, race, family history of breast/ovarian cancers, exercise, BMI, and heightQuestionnaire
Poole EM2011718/181,5480.8 (0.51–1.23)Cohort study7USAOvarian cancerNever vs. 20+ years rotating shift workNursesAge, duration of oral contraceptive use, parity, BMI, smoking status, tubal ligation history, menopausal status, family history of ovarian cancer, duration of breas tfeeding, and cohortQuestionnaire
Viswanathan AN2007515/53,4871.47 (1.03–2.1)Cohort study7USAEndometrial cancerNever vs. 20+ years rotating shift workNursesAge, age at menarche, age at menopause, parity, BMI duration of oral contraceptive use, use and duration of postmenopausal hormones, hypertension, diabetes, pack-years of smokingQuestionnaire
Akerstedt T2015463/1,36561.77 (1.03–3.04)Cohort study8SwedenBreast cancerNever vs. 21–45 yearsNAAge, education level, tobacco consumption, BMI, having children, coffee consumption, previous cancer, use of hormones including oral contraceptivesTelephone interview
Koppes LLJ20142,531/285,7230.87 (0.72–1.05)Cohort study8NetherlandBreast cancerNever vs. regular night workNAAge, origin, children in household education, occupation, job tenure (years)Personal interview
Natti J201248/1,6492.82 (1.196–6.645)Cohort study8FinlandUnclassified cancerDay vs. weekly night shiftNAAge, and smoking status, demographics and health- and work-related factorsFace-to-face interview
Schernhammer ES20061,352/115,0221.79 (1.06–3.01)Cohort study7USABreast cancerNever vs. 20+ years rotating shift workNursesAge, age at menarche, menopausal status, age at menopause, age at first birth and parity combined, age at first birth, BMI, current alcohol consumption, oral contraceptive use, postmenopausal hormone use, smoking status, benign breast disease, family history of breast cancer, and physical activityQuestionnaire
Pronk A2010349/69,4720.8 (0.5–1.2)Cohort study8ChinaBreast cancerNever vs. 17+ yearsNAAge, education, family history of breast cancer, number of pregnancies, age at first birth, and occupational physical activityInterview
Schernhammer ES2003602/78,5861.35 (1.03–1.77)Cohort study8USAColorectal cancerNever vs. 15+ years rotating shift workNursesAge in years; pack-years of smoking before age 30 in quintiles; BMI in five categories; physical activity in quintiles; regular aspirin use; colorectal cancer in parent or sibling; screening endoscopy during the study period; consumption of beef, pork, or lamb as a main dish; alcohol consumption status; total caloric intake in quintiles; use of postmenopausal hormones; menopausal status; and height in seven categoriesQuestionnaire
Vistisen HT20141,281/169,0111.68 (1.28–2.2)Cohort study5DenmarkBreast cancerNever vs. everNAShift workDatabase
Schernhammer ES20131,455/78,6121.28 (1.07–1.53)Cohort study7USALung cancerNever vs. 15+ years rotating shift workNursesAge, age at start smoking, cigarettes smoked per day, fruit intake, vegetable intake, BMI, measured as weight in kilograms divided by height in meters squared, menopausal status, hormone use among postmenopausal women, and oral contraceptive use, as well as environmental smoking exposures: parents smoking while living with them, years living with someone who smoked, exposure to smoking at work, and exposure to smoking at homeQuestionnaire
Gu F20155,413/74,8621.08 (0.98–1.08)Cohort study7USAUnclassified cancerNever vs. 15+ years rotating shift workNursesAge, alcohol consumption, physical exercise, multivitamin use, menopausal status and postmenopausal hormone use, physical exam in the past 2 years, healthy eating score (quintiles), smoking status, pack-years; BMI, and husband's educationQuestionnaire
Ren Z2014712/1,4541.34 (1.04–1.71)Case–control6ChinaBreast cancerNever vs. everNAAge, education, BMI, marital status, age at menarche, menopausal status, parity, activity, breastfeeding, family history of breast cancer, and other sleep factorsDatabase
Santi SA2015743/1,5181.7 (1.04–2.79)Case–control7CanadaBreast cancerNever vs. 10+ years rotating shift workNursesAge, family history, level of education, oral contraception use, alcohol consumption, number of births, and age of first menstruationQuestionnaire
Datta K201450/1501.509 (0.267–8.516)Case–control6South AsiaBreast cancerNever vs. everNAWorking in night shiftDirect interview
Lie JS2013172/6461.8 (1–3.1)Case–control7NorwayER+ breast cancerNever vs. 5+ years night shift workNursesAge at diagnosis, period of diagnosis, parity, family history of breast cancer in mother or sister, hormonal treatment in the previous 2 years before diagnosis, and frequency of alcohol consumption at the time of diagnosisTelephone interview
Lie JS201322/3462.8 (0.8–9.2)Case–control7NorwayER breast cancerNever vs. 5+ years night shift workNursesAge at diagnosis, period of diagnosis, parity, family history of breast cancer in mother or sister, hormonal treatment in the previous 2 years before diagnosis, and frequency of alcohol consumption at the time of diagnosisTelephone interview
Lie JS2006537/2,6802.21 (1.1–4.45)Nested case–control6NorwayBreast cancerNever vs. 30+ years night shift workNursesTotal employment time as a nurses and parityDatabase
Papantoniou K20151,708/3,4861.22 (0.82–1.81)Case–control8SpainBreast cancerNever vs. 15+ years night shift workNAAge, center, educational level, parity, menopausal status, family history of breast cancer, BMI, smoking status, oral contraceptive use, leisure time physical activity, alcohol consumption, sleep durationFace-to-face interview
Truong T20141,126/2,3001.32 (1.02–1.72)Case–control8FranceBreast cancerNever vs. everNAAge, study area, parity, age at first full-term pregnancy, age at menarche, family history of breast cancer, current use of hormonal replacement therapy, BMI, and tobacco and alcohol consumptionIn-person interview
Hansen J2012267/1,3022.1 (1.3–3.2)Nested case–control7DenmarkBreast cancerNever vs. 20+ years night shift workNursesAge, weight regularity, use of hormone replacement therapy, age at menarche, menstrual regularity, menopausal status, age at birth of first child, breast cancer in mother or sister, total duration of lactationInterview
Kloog I2011794/1,6791.359 (1.121–1.647)Case–control6Northern IsraelBreast cancerNo light vs. light at nightNALight at nightInterview
Hansen J20015,964/11,7501.7 (1.3–1.7)Case–control8DenmarkBreast cancerNever vs. 6+ years night shift workNAAge, social class, age at birth of first child, age at birth of last child, and number of childrenInterview
Grundy A20131,134/2,3132.21 (1.14–4.31)Case–control7CanadaBreast cancerNever vs. 30+ years night shift workNAYears of night shift historyQuestionnaire
Li Q201074/2010.9 (0.2–3.9)Case–control8USABreast cancerNever vs. everNAAge group, race, BMI, age at first menstrual period, family history of breast cancer, age at first full-term birth, months of lifetime breast feeding, cigarette smoking, alcohol drinking, and premenopausalInterview
Li Q2010289/5181.4 (0.5–4.3)Case–control8USABreast cancerNever vs. everNAAge group, race, BMI, age at first menstrual period, family history of breast cancer, age at first full-term birth, months of lifetime breast feeding, cigarette smoking, alcohol drinking, and postmenopausalInterview
Hansen J2012218/1,1172.1 (1–4.5)Nested case–control7DenmarkBreast cancerNever vs. 15+ years night shift workMilitary womenAge, hormone replacement therapy, number of childbirths, age at menarche, years of education, occasional sunbathing frequency, and tobacco smoking statusQuestionnaire
Kwon P20151,451/4,4910.88 (0.69–1.12)Nested case–control7ChinaBreast cancerNever vs. 30.6+ years night shift workTextile workersAge, smoking, parity, and endotoxinFactory personnel record review (80%), supervisor interviews (12%), and in-person employee or close relative interviews (8%).
Davis S2001813/1,6062.3 (1.2–4.2)Case–control8USABreast cancerNever vs. 4.6+ years night shift workNAParity, family history of breast cancer, oral contraceptive use, and recent discontinued use of hormone replacement therapyIn-person interview
Rabstein S2013857/1,7491.01 (0.68–1.5)Case–control8GermanyBreast cancerNever vs. everNAFamily history of breast cancer, hormone replacement use, number of mammograms, and estrogen receptor statusTelephone interview
Menegaux F20131,232/2,5491.4 (1.01–1.92)Case–control8FranceBreast cancerNever vs. 4.5+ years night shift workNAAge, study area, parity, age at first full-term pregnancy, age at menarche, family history of breast cancer, current hormonal replacement therapy, BMI, tobacco and alcoholIn-person interview
Bhatti P20131,101/2,9331.02 (0.74–1.42)Case–control8USAInvasive epithelial ovarian cancerNever vs. 7+ years night shift workNAAge at reference, county, reference year, duration of oral contraceptive use, number of full-term pregnancies, and BMI at age 30In-person interview
Wang P2015712/1,4541.34 (1.05–1.72)Case–control8ChinaBreast cancerNever vs. everNAAge, education, BMI, age at menarche, menopausal status, parity, physical activity, breast-feeding, family history of breast cancer, and other sleep factorsFace-to-face interview
Li W20151,709/6,4890.73 (0.66–0.82)Nested case–control6ChinaBreast cancerNever vs. everTextile workersAge at the beginning of follow-upReview of factory personnel records (80%), interviews of factory supervisors (12%), and in-person interviews of women or their relatives
O'Leary ES2006486/1,4440.32 (0.12–0.83)Case–control8USABreast cancerNever vs. 8+ years night shift workNAAge at reference date, parity, family history, education, and history of benign breast disease30-minute in-home interview
Fritschi L20131,202/2,9871.02 (0.71–1.45)Case–control7AustraliaBreast cancerNever vs. 20+ years night shift workNANight shift workQuestionnaire and a follow-up telephone interview
Schwartzbaum J2007236/1148,6611 (0.89–1.13)Cohort study8SwedenbCancerEver vs. neverNAAge, socioeconomic status, occupational position, and county of residenceInterview
Bauer SE201334,053/48,5111.12 (1.04–1.2)Case–control7USABreast cancerLow light at night vs. highNARace, tumor grade and stage, year of diagnosis, age at cancer diagnosis, Metropolitan Statistical Area (MSA) status, births per 1,000 women ages 15–50, MSA population mobility, population over 16 in the labor force, and prevalence of cigarette smokingInfrared light detection by a nighttime satellite
Kojo K200527/5441.52 (0.49–4.74)Nested case–control7FinlandBreast cancerNever vs. oftenCabin attendantsCumulative radiation dose, number of fertile years, parity, family history of breast cancer, alcohol consumption, disruption of sleep rhythm, and menstrual cycleQuestionnaire
Rafnsson V200335/1755.24 (1.58–17.38)Nested case–control6IcelandBreast cancer<5 years vs. ≥ 5 yearsCabin attendantsAge at first childbirth and length of employment, number of childrenEmployment history
Rafnsson V200335/1750.82 (0.34–1.97)Nested case–control6IcelandBreast cancer<5 years vs. ≥ 5 yearsCabin attendantsAge at first childbirth and length of employment, number of childrenEmployment history
Pukkala E2012559/8,2441.16 (1.06–1.25)Nested case–control5Finland, Iceland, Norway and Swedenb CancerCabin crew vs. general populationAirline cabin crewLength of employmentEmployment history
Linnersjö A200371/2,3241.01 (0.78–1.24)Nested case–control5Swedenb CancerCabin crew vs. general populationAirline cabin crewAge and calendar periodEmployment history
Reynolds P2002104/44,0211.05 (0.86–1.27)Cohort study5USAUnclassified cancerFlight attendants versus general populationFlight attendantsNoneHistorical AFA flight records extrapolated to California cohort
McElroy JA20064,033/9,3470.94 (0.62–1.44)Case–control8USABreast cancerShort duration of sleep per night vs. normalNAReference age, state, parity, age at first full-term pregnancy, family history of breast cancer, alcohol consumption, BMI, menopausal status, age at menopause, postmenopausal hormone use, education, and marital statusInterviews
Schernhammer E20149,140/193,3960.95 (0.77–1.17Cohort study5USABreast cancerNever vs. 30+ years rotating shift workNursesMultivariable adjustmentLarge prospective data sets
Marino JL2008812/2,1251.2 (1–1.5)Case–control5USAEpithelial ovarian cancerNever ns everNAMultivariable adjustmentIn-person interviews
Lie JS2011699/1,5941.3 (0.9–1.8)Nested case–control study8NorwayBreast cancerNever vs. 12+ years rotating shift workNursesAge, period of diagnosis, parity, family history of breast cancer in mother or sister (no/yes), and frequency of alcohol consumption at time of diagnosisTelephone interviews
Lie S2013513/1,2702.4 (1.3–4.3)Case–control5NorwayBreast cancerNever vs. 5+ years night shift workNursesNoneDatabase
Lahti TA20082,494/NAa1.02 (0.94–1.12)Cohort study6FinlandNon-Hodgkin lymphomaNever vs. everNAAge, social class, and cohort periodFinnish Job-Exposure Matrix (FINJEM)
Girschik J2013624/1,5431.05 (0.82–1.33)Case–control8AustraliaBreast cancerShort duration of sleep t vs. normalNAAge, number of children, age at first birth, breastfeeding, menopausal status, use of hormone replacement therapy, duration of use of hormone replacement therapy, alcohol consumption, comparative weight at age 30 years, ever use of melatonin, and physical activityQuestionnaire
Tsai RJ2014839/2,4571.34 (1.06–1.68)Case–control8USABreast cancerDaytime work vs. regular rotating shift workNAObesity, smoking status, alcohol consumption, race, income, education, health insurance coverage, and marital statusInterview
Tsai RJ20141,253/6,2380.98 (0.78–1.21)Case–control8USACervical cancerDaytime work vs. regular rotating shift workNAObesity, smoking status, alcohol consumption, race, income, education, health insurance coverage, and marital statusInterview
Tsai RJ20141,412/2,1761.17 (1.01–1.36)Case–control8USAColon cancerDaytime work vs. regular rotating shift workNAObesity, smoking status, alcohol consumption, race, income, education, health insurance coverage, and marital statusInterview
Chu CH2010408/2,0232.54 (1.37–4.7)Nested case–control study5ChinaBreast cancerNever vs. everNAPotential confoundersInterview
Luo J2012295/14,29330.79 (0.61–1.02)Cohort study8USAThyroid cancerShort sleep duration vs. normalNAAge at enrollment, ethnicity, educational level, smoking, BMI (weight (kg)/height (m)2), recreational physical activity, alcohol intake, family history of cancer, previous thyroid disease, history of hormone therapy use, depression score, and different treatment assignments for Women's Health Initiative clinical trialsQuestionnaire
Verkasalo PK2005242/12,2220.88 (0.11–6.91)Cohort study8FinlandBreast cancerShort sleep duration vs. normalNAAge, zygosity, social class, number of children, use of oral contraceptives, BMI, alcohol use, smoking, and physical activityQuestionnaire
Jiao L2013851/7,58281.36 (1.06–1.74)Cohort study8USAColorectal cancerShort sleep duration vs. normalNAAge, ethnicity, fatigue, hormone replacement therapy, waist-to-hip ratio, and physical activityQuestionnaire
Kakizaki M2008143/23,9951.67 (1.002–2.78)Cohort study8JapanBreast cancerShort sleep duration vs. normalNAAge, BMI, history of diseases, family history of cancer, job, marital status, education, cigarette smoking, alcohol consumption, time spent walking, total caloric intake, menopausal status, age at menarche, age at first delivery, number of deliveries, use of oral contraceptive drugs, use of hormone drugs except for oral contraceptive drugs (yes or no)Questionnaire
Tynes T1996140/2,1691.2 (1–1.4)Cohort study6Norwayb CancerNever vs. everRadio and telegraph operatorsShift work and duration of employmentDatabase
Pesch B2010749/1,5422.48 (0.62–9.99)Case–control8GermanyBreast cancerNever vs. 20+ years night shift workNAA potential selection bias using bootstrapping, family history of breast cancer, hormone replacement use, and number of mammogramsInterview
Bai Y2016613/140040.90 (0.66–1.23)Cohort study8ChinaUnclassified cancerNever vs. 20+ years night shift workNAAge, BMI, family history of cancer, alcohol drinking and smoking status, number of children, menopausal status, hormone replacement therapy, and contraception statusQuestionnaire
Cohen JM2015415/10,24840.90 (0.67–1.20)Cohort study8USAMelanomaShort sleep duration vs. normalNursesAge, number of sunburns, moles, hair color, family history of melanoma (yes, no), reaction to the sun, tanning, Caucasian ethnicity, ultraviolet flux (quintiles), snoringQuestionnaire
Travis RC20164,809/522,2461.00 (0.92–1.08)Cohort study8UKBreast cancerNever vs. everNASocioeconomic status, parity and age at first birth, BMI, alcohol intake, strenuous physical activity, family history of breast cancer, age at menarche, oral contraceptive use, smoking, living, with a partner, and use of menopausal hormone therapyQuestionnaire
Wegrzyn LR (NHS)c20175,971/7,85160.95 (0.77–1.17)Cohort study8USABreast cancerNever vs. 30+ years night shift workNursesAge, height, BMI, BMI at age 18, adolescent body size, age at menarche, age at first birth and parity combined, breastfeeding, type of menopause and age at menopause combined, menopausal hormone therapy, duration of estrogen alone menopausal hormone therapy, duration of estrogen and progesterone menopausal hormone therapy, first-degree family history of breast cancer, history of benign breast disease, alcohol consumption, physical activity, and current mammography useQuestionnaire
Wegrzyn LR (NHS2)c20173,570/114,5592.15 (1.23–3.73)Cohort study8USABreast cancerNever vs. 20+ years night shift workNursesAge, height, BMI, BMI at age 18, adolescent body size, age at menarche, age at first birth and parity combined, breastfeeding, type of menopause and age at menopause combined, menopausal hormone therapy, duration of estrogen alone menopausal hormone therapy, duration of estrogen and progesterone menopausal hormone therapy, first-degree family history of breast cancer, history of benign breast disease, alcohol consumption, physical activity, and current mammography useQuestionnaire
  • Abbreviations: NA, not available; BMI, body mass index.

  • aFrom the enrolled article, we could not obtain the accurate number of participants. Thus, in the preceding calculation, we missed the data. OR and corresponding 95% CI were extracted directly from the article.

  • bThese four studies reported the SIR for cancer overall among female night shifters and also reported on a number of different cancers, including, for example, breast cancer, colon cancer, cervix/uterus cancer, and other cancers.

  • cThis study examined associations between rotating night shift work and breast cancer in two prospective cohorts (NHS and NHS2).