Occupational factors and risk of preterm birth in nurses

We evaluated first-trimester exposures and the risk of preterm birth in the most recent pregnancy of participants of the Nurses' Health Study II.

Log binomial regression was used to estimate the relative risk (RR) for preterm birth in relation to occupational risk factors, such as work schedule, physical factors, and exposures to chemicals and x-rays, adjusted for age and parity.

Part-time work (

These data suggest that night work may be related to early but not late preterm birth, whereas physically demanding work did not strongly predict risk.