Association of occupational stress during pregnancy with premature birth and small for gestational age: A systematic review of observational studies

Abstract

Psychological stress during pregnancy can be considered as a predictor of premature birth, small for gestational age (SGA), and low birth weight (LBW). Owing to a rise in the number of working pregnant women in recent years, there has been increased focus on the possible effects of occupational stress on pregnancy outcomes. The aim of this review and meta-analysis was to investigate the associations of occupational stress during pregnancy with premature birth, SGA, and LBW. Methods A search through 6 databases (Ichushi-Web, CiNii, MEDLINE, CINAHL, Scopus, and PsycINFO) was conducted with "premature birth," "birth weight," and "occupational stress" as keywords for identifying relevant publications in Japanese and in English. The search covered the period between the beginning of each database and December 2019. The identified articles were screened based on the inclusion and exclusion criteria. We used DerSimonian-Laird method to integrate the results of articles included in the review. Results A total of eleven articles were included in this review. High occupational stress during pregnancy significantly correlated with a higher rate of premature birth in 2 out of 9 articles, with a higher rate of SGA in 2 out of 6 articles, and with a higher rate of LBW in 1 out of 2 articles. Meta-analyses showed that the rates of premature birth (odds ratio [OR]=1.2, 95% confidence interval [CI]=1.0-1.3) and SGA (OR=1.2, 95%CI=1.0-1.4) were significantly higher in women with the highest level of occupational stress, than in those with lower stress levels. Subgroup analyses indicated that moderate heterogeneity in the relationship between occupational stress and premature birth was partly explained by research regions. Conclusion The findings suggest that high occupational stress during pregnancy is associated with higher rates of premature birth and SGA. Improving the work environment and controlling workload may be required to prevent premature birth and SGA.