Objectives. We describe reported exposures to main categories of occupational agents and conditions in Spanish pregnant workers. Methods. Women were recruited at 12th week of pregnancy from main public gynaecological consults to be included in the INMA Spanish cohorts study (n = 2,058). Through personal interviews with structured questionnaires, information on working situation and working conditions during pregnancy was obtained. Results. Fifty percent of the women reported frequent exposure to physical load (standing, heavy lifting) and 45 % reported exposure to three or more indicators of job strain. Exposure to at least one physical agent (noise, vibrations, etc.) affected 25 % of the women. Exposure to chemicals was reported by 20 % of the women, mostly including solvents and cleaning products. Eight percent of the women worked at night shifts. Job strain was more prevalent in office workers and industrial operators. Industrial workers showed the highest prevalence of exposure to chemical and physical pollutants. Conclusions. Our data suggest that working conditions of pregnant women may need increased control in Spain.