OBSTETRICS Physical abuse during pregnancy and preterm delivery Teresa Rodrigues, MD; Lúcia Rocha, MPH; Henrique Barros, MD, PhD OBJECTIVE: This study was undertaken to assess the relationship be- tween physical abuse during pregnancy and preterm delivery. STUDY DESIGN: We conducted a hospital-based survey on physical abuse during pregnancy, which included 2660 women with consecu- tive live births. Women were interviewed and violence was assessed using the Abuse Assessment Screen. Data on sociodemographic, be- havioral, and obstetric variables were also obtained. Mothers of pre- term (37 weeks; n = 217) were contrasted with mothers of term newborn infants (n = 2428). Logistic regression analysis was per- formed to estimate adjusted odds ratios. RESULTS: Twenty-four percent of mothers of preterm newborn infants had experienced physical abuse during pregnancy compared with 8% of mothers of term newborn infants (P  .0001). Violence was asso- ciated with preterm birth even after controlling for age, marital status, education, income, parity, planned pregnancy, antenatal care, smok- ing, alcohol, and illicit drugs use (odds ratio = 3.14, 95% confidence interval, 2.00-4.93). CONCLUSION: Women who have had physical abuse during preg- nancy present a large increase in the risk of preterm delivery, independently from a large set of sociodemographic and behav- ioral characteristics usually recognized as determinants of preterm birth. Key words: physical abuse, pregnancy, preterm, violence Cite this article as: Rodrigues T, Rocha L, Barros H. Physical abuse during pregnancy and preterm delivery. Am J Obstet Gynecol 2008;198:171.e1-171.e6. P reterm birth remains an unsolved rel- evant public health issue. 1 Knowledge about etiologic factors is insufficient, effec- tive prophylactic interventions are un- available, and in most countries, increasing rates are observed. 2 Only few factors were established as pre- term birth determinants and most are not amenable to intervention, like ethnicity, multiple pregnancy, or a previous preterm delivery. This led to a resurgence of interest on the role of social and environmental factors like racism, violence, poverty, stress, and physical exertion in the occur- rence of preterm birth and the design of preventive strategies. 1,3 Studies in Europe and North Amer- ica showed that the prevalence of vio- lence against pregnant women varied between 0.9% and 22.0%, 4 and physi- cal abuse is increasingly reported as a potentially modifiable risk factor for pregnancy adverse outcome. 5-8 Few studies on the association between physical abuse and preterm birth have been reported, and those that have found an effect were mainly conducted among low-income and teenage moth- ers. 9-12 Few population-based studies with a large sample size and allowing control for several confounding vari- ables have been conducted, and some have not yielded a significant associa- tion between physical violence and preterm birth. 13,14 Differences in pop- ulation characteristics and sample size, varying definitions of physical violence and birth outcome, and different study design and control for confounding may also explain the discrepant find- ings. In this study we aimed to assess and clarify the relationship between physical abuse during pregnancy and preterm delivery. MATERIALS AND METHODS This survey included 2660 white women consecutively delivered of live singleton infants, at the Department of Obstetrics of Hospital de São João, in Porto, during a 10-month period in 1999-2000. This level III teaching hospital admits almost all pregnant women from the neighbor- hood area and is a referral hospital for several level II units. In the first 96 hours after delivery, women were invited to participate and asked written informed consent. The central study hypothesis—the associa- tion between physical abuse and adverse pregnancy outcome—was not explicitly presented during the study description to eligible participants. Information was obtained by face-to-face interview. All interviews were performed by trained social workers in a private setting at the hospital, and women were guaranteed confidentiality. There was no refusal to participate. Participants completed a question- naire comprising questions on sociode- mographic (age, education, employ- ment status, cohabitation status with infant’s father, and family income), cur- rent pregnancy (parity, anthropomet- rics, antenatal care use, and intention to From the Department of Hygiene and Epidemiology, University of Porto Medical School (Drs Rodrigues and Barros), and the Department of Obstetrics and Gynecology, Hospital S. João (Dr Rodrigues and Ms Rocha), Porto, Portugal. Received Dec. 4, 2006; revised Jan. 30, 2007; accepted May 11, 2007 Reprints: Teresa Rodrigues, Serviço de Higiene e Epidemiologia, Faculdade de Medicina do Porto, Al. Prof. Hernani Monteiro, 4200-319 Porto; tererod@med.up.pt 0002-9378/$34.00 © 2008 Mosby, Inc. All rights reserved. doi: 10.1016/j.ajog.2007.05.015 See Journal Club, page 239 Research www. AJOG.org FEBRUARY 2008 American Journal of Obstetrics & Gynecology 171.e1