BMC Public Health 2006, 6:109 http://www.biomedcentral.com/1471-2458/6/109 reflected by the large confidence intervals around the point estimates. Thus, they reduced the ability to obtain significant statistical results with some of the variables. We cannot assume that the findings of this study can be generalised to other rural areas elsewhere. Though the study represents a rural setting, where the majority of the population is less educated, with no stable income, cul- tural and traditional customs prevail. The estimated prevalence might reflect the prevalence in the general population within the catchment area, as shown by validations of the ANC-based and population- based estimates [6,9,10]. These validations have been showing an overestimation of the prevalence among younger women and underestimation in older age group. Nevertheless, the HIV epidemic has been shown to be het- erogeneous in terms of intensity, pace and impact within sub-regions [31]. Similar patterns may be found within different areas of the same country (8, 22, 31). Thus, local monitoring may reveal inherent patterns that can be opti- mised for preventive strategies. There have been mixed conclusions on the risk of HIV with educational attainment, but most studies from sub- Saharan Africa have shown increased schooling to be associated with increased risk of HIV [7,9,32]. Studies that are more recent however, have indicated that this associa- tion changed direction in the 1990s. In young people, the likelihood of infection was higher in those with little edu- cation compared to those with more education [7,9,32,33]. The HIV prevalence tended to decline with educational attainment in our data. Women with an edu- cation of more than seven years have lower parity com- pared to those with less years of schooling in this setting, confirming less number of children with higher educa- tional attainment, but not with increased odds of HIV infection. The effect of reduced fertility because of HIV in an area of low prevalence is likely to be minimal since these are recent infections. The situation might change with time as the epidemic matures in this setting. However, its direc- tion is uncertain, as educational data from antenatal clin- ics are prone to bias due to attendance influence by fertility and educational attainment. The general deficit in HIV related knowledge is not surprising since HIV related preventive services in the local area were introduced just recently as part of the larger preventive programme. History of either genital sores or foul smelling genital dis- charge was found to be significantly associated with HIV in this study, OR 6.8 (95%CI: 2.78–16.66). This is in accordance with other studies [34,35]. Prevalent STIs enhance HIV transmission by increasing susceptibility through compromising mucosal integrity [35]. We are inclined to consider high prevalence of ulcerative STIs such as chancroid, syphilis and herpes simplex virus 2 [35-37], due to their greater disruption of genital mucosa. The effects of STI control have been suggested to be bene- ficial at the beginning of an HIV epidemic in other studies [38,39]. This is a strategy also applied in this local setting to prevent the spread of HIV Women who reported more than one lifetime sexual part- ner had four times likelihood of being HIV positive, OR 4.3 (95%CI: 1.42–12.77). Few women (5%) report more than one lifetime sexual partner. The general tendency of women under-reporting sexual partners has been reported by many and elsewhere in Tanzania [40]. Women aged above 20 years who had their first pregnancy at ages younger than 18 years, have a higher HIV preva- lence (4.4% CI: 1.20–4.40) compared to those who have their first pregnancy at ages above 18 years (1.5% CI: 0.13–0.72). However, the proportions of early pregnan- cies of these women are similar to the current teenage pregnancies in the study 12.7% (164/1296). Pregnancies before 18 years of age indicate a younger sexual debut, which has been associated with increased risk of HIV infection [41-43]. Our findings suggest early pregnancies are common in this area at similar proportions in both remote and rural clinics, yet the HIV prevalence had remained relatively low compared to other rural areas in Tanzania [44]. In conclusion, scaling up HIV prevention efforts is man- datory in order to prevent the imminent escalation of the HIV epidemic highly associated with history of STIs, mul- tiple sexual partners and pregnancies at younger age. The observed low level of HIV related knowledge and the fact that few had ever used a condom underscores the urgency for large-scale HIV related programmes. Including remote rural sites as part of routine ANC surveillance is crucial in order to discover imminent silent epidemics such as the one described in this paper. Establishing quality surveil- lance among pregnant women will allow monitoring of trends and prevent infections to new-borns. Population- based household surveys, behavioural surveillance and relevant social studies would also be necessary. This will allow a wider representation of the risk factors and local context of HIV in the general population (including men and women) to enable customised HIV prevention. Competing interests The author(s) declare that they have no competing inter- ests. Page 7 of 9 (page number not for citation purposes)