Physical exertion at work during pregnancy did not increase risk of preterm delivery or fetal growth restriction

摘要

Maria, 28 years old, is concerned that her work could affect her unborn baby. She is at 28 weeks of gestation. She has been a school cleaner for 4 years. She has 2 healthy children, aged 5 and 3 years, but her younger child was born at 35 weeks and was borderline for size at that gestational age. She works 35 hours/week, rotating day and evening shifts. There has been no problem with the pregnancy. At work, she stands and walks continuously, lifts vacuum cleaners or buckets weighing 10 kg about 15 times per shift, and mops and scrubs manually for half of each shift. Her husband has a back problem and is off work. At home she does all the housework and gets to bed by 1 am. She is of average height and weight and does not smoke. Certain limitations of the study by Pompeii et al restrict its applicability. Only 53% of the eligible cohort participated fully. Exposure data were gathered for the 2 longest held jobs but not for all jobs and not for unpaid work. Full quantification of the exposures was done for only a minority of women near the end of the study; for the remainder, exposures were estimated. For lifting, the cut point of >=13 times/week is low for interpreting the jobs of many workers. Apart from lifting, manual work was not studied. The study did not consider shift work, making it difficult to interpret the observed effect of night work. On the other hand, the study's prospective design is a strength in that women were asked about work while they were still pregnant.One should also consider previous good quality cohort studies on this topic.Although results have been conflicting, some evidence exists of adverse effects of working conditions on obstetrical outcomes; however, relative risks are not likely to exceed 2.Although her prior history of preterm delivery increases the risk of recurrence, Maria should be advised (based on combined evidence from good quality studies) that the possible effects of physical exertion in her work (and unpaid work) need to be balanced with those that could be associated with a drop in income (and change in socioeconomic status) if she stopped doing her regular work.