ArticleOccupational and environmental medicine2003
Shift work and subfecundity: a causal link or an artefact?
Article in Occupational and environmental medicine, 2003. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 25 papers, 1 of them a synthesis that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
25 citing papers in PubMed, 1 synthesis or guideline pooled it, 68 citations in OpenAlex.
- Association of psychosocial factors at work with fertility and menstrual disorders: A systematic review.Japan journal of nursing science : JJNS · 2025Pooled it
- Associations between daytime napping and parameters of ovarian reserve among women undergoing assisted reproductive technology.BMC women's health · 2026Article
- Fertility in a prospective Canadian cohort of women in the welding and electrical trades.Occupational and environmental medicine · 2025Article
- The association between sleep and fecundability: a Danish preconception cohort study.European journal of public health · 2025Article
- Impact of night shift work on women's fertility, pregnancy and menopause.Frontiers in sleep · 2025Review
- Role of circadian clock in female embryo implantation.Frontiers in cell and developmental biology · 2025Review
- Preconception sleep duration, sleep timing, and shift work in association with fecundability and live birth among women with a history of pregnancy loss.Fertility and sterility · 2023Article
- The current situation and future directions for the study on time-to-pregnancy: a scoping review.Reproductive health · 2022Article
- The association between work hours, shift work, and job latitude with fecundability: A preconception cohort study.Journal of occupational health psychology · 2022Article
- The Association Between Long Working Hours and Infertility.Safety and health at work · 2021Article
- Night Shift Work and Fecundability in Late Reproductive-Aged African American Women.Journal of women's health (2002) · 2021Article
- Shiftwork and Light at Night Negatively Impact Molecular and Endocrine Timekeeping in the Female Reproductive Axis in Humans and Rodents.International journal of molecular sciences · 2020Review
- IMPACT survey: IMpaired fecundity in Physicians and Association with Clinical Time.Journal of the American College of Emergency Physicians open · 2020Article
- Development and psychometric evaluation of the women shift workers' reproductive health questionnaire: a sequential exploratory mixed-method study.Reproductive health · 2020Article
- Anti-Müllerian hormone levels in nurses working night shifts.Archives of environmental & occupational health · 2020Article
- Female sleep patterns, shift work, and fecundability in a North American preconception cohort study.Fertility and sterility · 2019Article
- Development and psychometric evaluation of a women shift workers' reproductive health questionnaire: study protocol for a sequential exploratory mixed-method study.Reproductive health · 2018Article
- Occupational factors and markers of ovarian reserve and response among women at a fertility centre.Occupational and environmental medicine · 2017Article
- Work schedule and physical factors in relation to fecundity in nurses.Occupational and environmental medicine · 2015Article
- Menstrual characteristics and night work among nurses.Industrial health · 2015Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors at 3 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
aimsThe Danish National Birth Cohort (DNBC) was used to examine whether shift work is associated with reduced fecundity as estimated by time to pregnancy (TTP).
methodsFrom 1 March 1998 to 1 May 2000, 39 913 pregnant women were enrolled in the DNBC. Data on job characteristics and TTP (0-2, 3-5, 6-12, and >12 months) were used for 17 531 daytime workers and 3907 shift workers who had planned the pregnancy. Fecundity odds ratios (ORs) were calculated with 95% confidence intervals using the discrete time survival analysis techniques performed by logistic regression. An OR above 1 expresses a shorter TTP and then a higher fecundity. Potential confounders, such as age at conception, gravidity, prepregnant body mass index, smoking, and alcohol consumption, as well as occupational characteristics, were also included in the model.
resultsFixed evening workers and fixed night workers had a longer TTP. Compared with daytime workers, the adjusted ORs were 0.80 (95% CI 0.70 to 0.92) for fixed evening workers, 0.80 (95% CI 0.63 to 1.00) for fixed night workers, 0.99 (95% CI 0.91 to 1.07) for rotating shift (without night) workers, and 1.05 (95% CI 0.97 to 1.14) for rotating shift (with night) workers. When analysis was restricted to nulliparous women, the estimates remained unchanged. The proportions of unplanned pregnancies and contraceptive failures were higher among fixed evening and fixed night workers.
conclusionsThere was no unequivocal evidence of a causal association between shift work and subfecundity. The slightly reduced fecundity among fixed evening workers and fixed night workers may be mediated by pregnancy planning bias or differential options for sexual contacts.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.