This study examines factors associated with the use of biomedical care during pregnancy in Guatemala, focusing on the extent to which complications in an ongoing or previous pregnancy affect a woman's decisions to seek care. The findings, based on multilevel models, suggest that obstetrical need, as well as demographic, social, and cultural factors, are important predictors of pregnancy care. In contrast, measures of availability and access to health services have modest effects. The results also suggest the importance of unobserved variables--such as quality of care--in explaining women's decisions about pregnancy care. These results imply that improving proximity to biomedical services is unlikely to have a dramatic impact on utilization in the absence of additional changes that improve the quality of care or reduce barriers to access. Moreover, current efforts aimed at incorporating midwives into the formal health-care system may need to extend their focus beyond the modification of midwife practices to consider the provision of culturally appropriate, high-quality services by traditional and biomedical providers alike.