Relationships between physical abuse during pregnancy and risk factors for preterm birth among women in Manitoba.

OBJECTIVE: To describe the prevalence and correlates of physical abuse during the year of pregnancy and to explore the association between physical abuse and other risk factors for preterm birth.
DESIGN: Secondary analysis of data from a case-control study of risk factors for preterm birth.
SETTING: Two tertiary care hospitals in the Canadian province of Manitoba. PARTICIPANTS: Six hundred eighty postpartum women who delivered a live singleton newborn after spontaneous onset of labor. MAIN OUTCOME MEASURES: Instruments included the Abuse Assessment Screen, Prenatal Psychosocial Profile, Perceived Stress Scale, and a questionnaire to collect data on demographic characteristics, complications during pregnancy, and lifestyle behaviors.
RESULTS: Sixty-four women (9.4%) reported being physically abused during the year of pregnancy. Abused women were significantly more likely to be younger, single, of lower income, and less educated than nonabused women. Significant correlates of abuse, after adjusting for other factors in a logistic regression, included the following: illicit drug use, low support from partner, moving two or more times in the past year, high life event stress, bladder infection during pregnancy, Aboriginal race/ethnicity, and single marital status.
CONCLUSION: This study suggests that physical abuse during pregnancy is associated with other risk factors for preterm birth, particularly stress and behavioral risk factors such as substance abuse.