Preventive withdrawal

• The overall workload is evaluated by means of the cumulative set of occupational conditions, the level of physical activity and the level of energy expenditure.
• Exposure to an increased number of occupational conditions is linked to increased preterm deliveries and, to a lesser extent, to increased small-for-gestational-age births.
• Increases in the incidence of low-birthweight and high blood pressure during pregnancy are suspected in the presence of two or three occupational conditions. 
• Excessive preterm deliveries and low-birthweights are suspected during exposure to high and moderate levels of physical activity, respectively.
• Different effects of energy expenditure are suspected, i.e., lower birthweight, an increase in spontaneous abortions and a higher incidence of high blood pressure during pregnancy in the presence of a high level of activity, and increased small-for-gestational-age births in the case of moderate and high levels of…

Objectives
To summarize the available scientific information on the effects of workplace noise exposure during pregnancy. The studied effects on pregnancy are: spontaneous abortion (SA), stillbirth (SB), congenital anomalies (CA), preterm delivery (PTD), low birth weight (LBW), small-forgestational- age (SGA) infant, pre-eclampsia (PE) and gestational hypertension (GHT). The effect of workplace noise during pregnancy on the child's hearing is also addressed.

Method
First, two bibliographic searches, one in Medline and the other in Embase, were performed to identify the original epidemiological studies that evaluated the effects of workplace noise on pregnancy. Studies published in French or in English between 1970 and August 2008 were selected. The bibliographies of the articles and the personal files of the author completed the list of the articles for consultation. There was no systematic search for unpublished material. The pr…