Women who are physically abused by an intimate partner during pregnancy have significantly elevated odds of experiencing certain adverse pregnancy outcomes, according to a study in two hospitals in Vancouver, British Columbia.¹ Physical abuse was found to be associated with an increased risk of hemorrhage in the second or third trimester, intrauterine growth restriction and perinatal death (odds ratios, 3.1-8.1). In the absence of physical abuse, fear of an intimate partner was not associated with any of the pregnancy outcomes studied.

To determine whether exposure to or fear of intimate partner violence is associated with certain negative pregnancy outcomes, researchers trained obstetric nurses from two Vancouver hospitals to gather relevant information from women admitted for delivery between January 1, 1999, and December 31, 2000. During routine patient assessment, the nurses asked women "Since you've been pregnant, have you been hit, slapped, kicked or otherwise physically hurt by a current or former intimate partner?" and "Have you been afraid of a current or former intimate partner during your pregnancy?" Interviews were conducted in private and in the same language spoken by the patient.

Researchers considered women to have experienced a specific adverse pregnancy outcome if such a condition was documented in the women's medical charts. The pregnancy outcomes studied were antepartum hemorrhage after the first trimester, preterm labor or delivery (i.e., before 37 weeks' gestation), intrauterine growth restriction (indicated by an infant's birth weight in the 10th percentile or less) and perinatal death (fetal death after 20 weeks' gestation or death of a newborn before hospital discharge). Women's demographic information, substance use histories and reproductive histories were collected from medical charts. Data were analyzed using logistic regression.

Of the 9,794 women who delivered infants at 20 or more weeks' gestation during the study period, 4,750 were interviewed; 56 reported having been physically abused by an intimate partner during the pregnancy, and 69 reported being afraid of a partner. Significantly greater proportions of women who were exposed to abuse or who feared a partner than of others were younger than 25 (32% vs. 11%), single parents (42% vs. 6%), members of the First Nations (24% vs. 2%), in the lowest quintile of household income (69% vs. 35%), users of alcohol or illicit drugs (14-17% vs. 2%), or current smokers (30% vs. 5%). In addition, 33% of women who were exposed to abuse or who feared a partner had had at least one induced abortion, in comparison with 21% of other women.

Among the women in the sample, 824 experienced one of the adverse pregnancy outcomes studied: 126 antepartum hemorrhage, 233 preterm labor, 308 preterm delivery, 134 intrauterine growth restriction and 23 perinatal death. In multivariate analysis adjusted for income and race or ethnicity, women who were physically abused during pregnancy were significantly more likely than others to have experienced antepartum hemorrhage (odds ratio, 3.8), intrauterine growth restriction (3.1) and perinatal death (8.1). In analyses additionally adjusted for use of alcohol, illicit drugs or tobacco, women who had been physically abused continued to have an elevated risk of antepartum hemorrhage (3.5) and perinatal death (7.3); the odds ratio for intrauterine growth restrictions was elevated (2.8), although it was only marginally significant. Fear of an intimate partner was not significantly associated with adverse pregnancy outcomes in univariate models and, thus, was not included in further analyses.

When the researchers stratified the analyses to further examine the associations between substance use, physical abuse and adverse pregnancy outcomes, they found that physical abuse was significantly associated with an increased risk of antepartum hemorrhage among nonusers of alcohol, illicit drugs or tobacco (relative risks, 3.5-3.8) and of intrauterine growth restriction among users of those substances (5.3-7.1). Perinatal death was positively associated with physical abuse among nonusers of alcohol (10.1) and among users of illicit drugs (5.1).

The researchers acknowledge the possibility of selection bias or underreporting in the study because nurses were not able to communicate with all patients in their own language or in private. Even so, they note that their study confirms the previously reported association between physical abuse and intrauterine growth restriction and reveals an association with antepartum hemorrhage and perinatal death. The researchers conclude that "intimate partner-perpetrated violence in pregnancy is preventable" and suggest that women be asked about exposure to intimate partner violence during prenatal visits to "facilitate access to information and resources."--J. Rosenberg

REFERENCE

1. Janssen PA et al., Intimate partner violence and adverse pregnancy outcomes: a population-based study, American Journal of Obstetrics and Gynecology, 2003, 188(5):1341-1347.