BMC Public Health 2007, 7:268 http://www.biomedcentral.com/1471-2458/7/268 hensive data on these variables. A possible limitation of this data from a tertiary level perinatal centre in this area is that some adverse outcomes may be overly present, but this is probably the case particularly in the reference pop- ulation. Furthermore, estimation of gestational age in pregnancies with a lack of antenatal care may not be as accurate as normally. However, inaccuracy in assessing the risk of prematurity was overcome by the high percent- age of low birth weight infants and the lower mean birth weights found in women lacking in antenatal care. The high amount of preterm births (39.6%) in the group of women having only 1–5 visits at antenatal care is partly the explanation for few visits. However, the outcome was very much alike in the group of women totally lacking antenatal care. Accordingly, compared with a prior Finn- ish study [32], the risks of prematurity, NICU-treatments and perinatal death were higher in our study, probably since we did not adjust the number of antenatal visits according to gestational age. Moreover, the background data for women not attending antenatal care was collected at the time of the birth, may have underreporting as a source of error, depending on the pregnancy outcome. Furthermore, by definition, distinguishing confounding factors from mediating factors as regards lack of antenatal care and adverse pregnancy outcomes is difficult. How- ever, pregnancy outcome measures in the groups studied were compared both before and after adjusting for these factors, to overcome the difficulty brought about by either the confounding or mediating roles of the known obstet- ric risks significantly associated with under-attending antenatal care. The role of domestic violence as an etiological factor needs future investigation. Other possible explanations that require future research are psychiatric disorders and ideological reasons for refusing antenatal care (natural- ism, avoidance of technology, religion). Moreover, it would be interesting to investigate the children of the women who excluded themselves from maternity care. Conclusion In conclusion, the results of this study highlight to two things: First, it is important to recognize women under- attending antenatal care during pregnancy as high-risk obstetric patients who need extra surveillance during delivery, support when going home with the newborn, and probably support in responsible health behavior in the future. Second, our results underline the beneficial role of maternity care not only as regards recognizing and treating pregnancy pathology, but also in terms of a resource of health education and an environment for con- fidential handling of sensitive issues, such as unwanted pregnancy or domestic violence. Competing interests The author(s) declare that they have no competing inter- ests. Authors' contributions All authors (KR, NH, and SH) participated in designing the study, analyzing the results and writing the manu- script, KR coordinated the study. All authors read and approved the final manuscript. Acknowledgements The authors would like to thank Olavi Kauhanen, EDB designer of Kuopio University Hospital, department of obstetrics and gynecology for perform- ing the statistical analyses. References 1. Villar J, Bergsjo P: Scientific basis for the content of routine antenatal care. I. Philosophy, recent studies, and power to eliminate or alleviate adverse maternal outcomes. Acta Obstet Gynecol Scand 1997, 76(1):1-14. 2. Carroli G, Villar J, Piaggio G, Khan-Neelofur D, Gulmezoglu M, Mug- ford M, Lumbiganon P, Farnot U, Bersgjø P, WHO Antenatal Care Trial Research Group: WHO systematic review of randomised controlled trials of routine antenatal care. Lancet 357(9268):1565-70. 2001; May 19; 3. Kunzel W, Misselwitz B: Unexpected fetal death during preg- nancy – a problem of unrecognized fetal disorders during antenatal care? Eur J Obstet Gynecol Reprod Biol 110(Suppl 1):S86-92. 2003; Sep 22; 4. National Centre for Women's and Childrens' Health: Antenatal care: routine care for the healthy pregnant women. Clinical guideline First edi- tion. London: RCOG press; 2003. 5. Villar J, Khan-Neelofur D: Patterns of routine antenatal care for low-risk pregnancy. Cochrane Database Syst Rev 2000, 2(2):CD000934. 6. Kaunitz AM, Spence C, Danielson TS, Rochat RW, Grimes DA: Peri- natal and maternal mortality in a religious group avoiding obstetric care. Am J Obstet Gynecol 150(7):826-31. 1984; Dec 1; 7. Hildingsson I, Waldenstrom U, Radestad I: Women's expectations on antenatal care as assessed in early pregnancy: number of visits, continuity of caregiver and general content. Acta Obstet Gynecol Scand 2002, 81(2):118-125. 8. Kupek E, Petrou S, Vause S, Maresh M: Clinical, provider and soci- odemographic predictors of late initiation of antenatal care in England and Wales. BJOG 2002, 109(3):265-273. 9. McCaw-Binns A, La Grenade J, Ashley D: Under-users of antena- tal care: a comparison of non-attenders and late attenders for antenatal care, with early attenders. Soc Sci Med 1995, 40(7):1003-1012. 10. Hartikainen AL: Äitiysneuvolakäynnit lisääntyvät jatkuvasti- olisiko aihetta toiminnan arviointiin? (Antenatal care visits are in constant increase – is there need for reconsidering?). Suom Lääkäril 2003, 22:2437-2440. 11. STAKES: Perinatal Statistics of Finland. Perinataalitilastot. 2003 [http://www.stakes.info/2/1/2,1,1.asp]. 12. Stakesin perhesuunnittelun ja äitiyshuollon asiantuntijaryhmä, Kirsi Viisainen (toim.): Seulontatutkimukset ja yhteistyö äitiyshuol- lossa, suositukset 1999. (Screenings and collaboration in maternity care, recommendations 1999). Volume 34. Jyväskylä: STAKES Oppaita; 1999. 13. Hemminki E, Blondel B, Study Group on Barriers and Incentives to Prenatal Care in Europe: Antenatal care in Europe: varying ways of providing high-coverage services. Eur J Obstet Gynecol Reprod Biol 2001, 94(1):145-148. 14. Richardus JH, Graafmans WC, Verloove-Vanhorick SP, Mackenbach JP, EuroNatal International Audit Panel, EuroNatal Working Group: Differences in perinatal mortality and suboptimal care between 10 European regions: results of an international audit. BJOG 2003, 110(2):97-105. Page 7 of 8 (page number not for citation purposes)