文章基本信息

标题：Work Activity in Pregnancy, Preventive Measures, and the Risk of Delivering a Small-for-Gestational-Age Infant
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作者：Agathe Croteau ; Sylvie Marcoux ; Chantal Brisson 等
期刊名称：American journal of public health
印刷版ISSN：0090-0036
出版年度：2006
卷号：96
期号：5
页码：846-855
DOI：10.2105/AJPH.2004.058552
语种：English
出版社：American Public Health Association
摘要：Objectives. We undertook a case–control study to evaluate whether some occupational conditions during pregnancy increase the risk of delivering a small-for-gestational-age (SGA) infant and whether taking measures to eliminate these conditions decreases that risk. Methods. The 1536 cases and 4441 controls were selected from 43898 women who had single live births between January 1997 and March 1999 in Québec, Canada. The women were interviewed by telephone after delivery. Results. The risk of having an SGA infant increased with an irregular or shift-work schedule alone and with a cumulative index of the following occupational conditions: night hours, irregular or shift-work schedule, standing, lifting loads, noise, and high psychological demand combined with low social support. When the conditions were not eliminated, the risk increased with the number of conditions ( P _trend =.004; odds ratios=1.00, 1.08, 1.28, 1.43, and 2.29 for 0, 1, 2, 3, and 4–6 conditions, respectively). Elimination of the conditions before 24 weeks of pregnancy brought the risks close to those of unexposed women. Conclusions. Certain occupational conditions experienced by pregnant women can increase their risk of having an SGA infant, but preventive measures can reduce the risk. Fetal growth retardation increases infant mortality and morbidity, 1 may lead to neurodevelopmental deficits, 2 ^, 3 and generates high social costs. 4 Maternal risk factors for this condition include smoking, 1 ^, 2 ^, 5 ^– 8 medical conditions, 1 ^– 3 ^, 5 ^– 7 and social factors. 5 ^, 8 ^, 9 Occupational factors are also considered to increase the risk. A number of epidemiological studies 10 ^– 31 have observed a significant effect of some occupational conditions on fetal growth, including long hours of work, 13 ^– 20 shift work, 20 ^, 21 prolonged standing, 12 ^, 15 ^, 16 ^, 19 ^, 25 ^, 26 ^, 28 lifting loads, 20 and high psychosocial stress. 30 ^, 31 However, some studies showed no effect. 10 ^, 11 ^, 17 ^, 18 ^, 23 In a number of studies, limitations related to the measurement of exposure may have led to underestimation of the true effect. These limitations include having a reference group that includes moderately exposed workers, 10 ^– 12 ^, 14 ^, 15 ^, 17 ^, 18 ^, 20 ^– 24 ^, 27 measuring occupational conditions on the basis of job title, 25 and failing to take into account changes in occupational conditions that occur during pregnancy. 10 ^, 11 ^, 13 ^, 15 ^, 17 ^, 19 ^– 22 ^, 25 ^– 27 ^, 30 ^, 31 The latter limitation is important because previous studies have suggested that workers most heavily exposed during early pregnancy are more likely to experience a reduction in exposure over the course of the pregnancy or to take earlier antenatal leave. 12 ^, 14 ^, 16 ^, 23 ^, 28 ^, 29 In the province of Québec, Canada, pregnant workers whose working conditions present a danger to the worker or the fetus have a legal right to be assigned to other tasks. 32 For each pregnant worker the pertinence of this measure is determined by the Commission de la santé et de la sécurité au travail, the governmental agency for health and safety at work, after an evaluation of the worker’s working conditions by a public health physician. Recourse to preventive measures does not depend on the union’s or employer’s willingness or on the woman’s health. If the employer cannot reassign the pregnant worker to a safe job, the worker is entitled to withdraw from work and collect 90% of her salary until 4 weeks before the expected birthdate. After that, she can benefit from the law of parental insurance and return to her regular job after maternity leave. Discrepancies in the application of the law across the province offer a favorable context in which to evaluate the effect of elimination of hazardous occupational conditions. We measured the association between some occupational conditions (schedule, posture, physical effort, psychosocial factors), both individually and cumulatively, and the risk of delivering a small-for-gestational-age (SGA) infant. We also assessed whether the elimination of these occupational conditions by preventive measures (change in working conditions or preventive withdrawal) before 24 or after 23 weeks of pregnancy modified the risk.