mon behavior and is more common among African American women than white women, consistent with the increased prevalence of bacterial vaginosis (BV) and preterm birth among African American women (Bruce et al., 2000). Furthermore, douching alters the vaginal microflora and may well facilitate the passage of vaginal pathogens to the upper reproductive tract, which contributes to inflammation and, possibly, to preterm birth. Few empirical evaluations of this hypothesis have been conducted thus far.
Women rarely douche during pregnancy, so the analyses have focused on douching during the period before pregnancy begins. Bruce et al. (2002) reported no association, after adjustment for confounders, between douching at any time before pregnancy and preterm birth, with ORs ranging from 0.7 to 1.1. However, among the small proportion of women who did report that they douched during pregnancy, the OR for preterm birth was 1.9 (95% CI 1.0–3.7). In another study (Fiscella et al., 2002), frequent and long durations of douching before pregnancy were found to be associated with an increased risk of preterm birth. Given the racial disparity in douching practices and the high degree of plausibility that douching influences pathways linked to preterm delivery, continued evaluations of the effects of this behavior are warranted.
In 1985 the Institute of Medicine (IOM) issued a report on low birth weight that concluded that stress was one promising avenue for future research (IOM, 1985). Since then, the findings of many more investigations have been published, as have numerous reviews, partial reviews, and commentaries on this area of research (Istvan, 1986; Kramer et al., 2001a; Lederman, 1986; Lobel, 1994; Paarlberg et al., 1995; Savitz and Pastore, 1999). However, existing reviews are outdated because of the burgeoning papers that have been published since the year 2000. This reflects the high level of scientific interest and public health attention to the topic of psychosocial factors and preterm delivery, especially research on stress and preterm delivery. This section summarizes the scientific findings on stress (including racism as a stressor), social support, and the intendedness of a pregnancy and their relation to the occurrence of preterm delivery.
Stress is defined as demands that tax or exceed the adaptive capacity of an organism and that result in psychological and biological changes (Cohen and Syme, 1985). This definition includes both environmental demands and the responses to them at multiple levels of analysis (cognitive, affective, immune, endocrine, cardiovascular, and so on). The breadth of this con-