Major Finding: Some 11% of women reported abuse in the period surrounding pregnancy. Abused women who were younger than age 20 or were aged 35 or older, or who were depressed before pregnancy, were more than twice as likely to have postpartum depression.
Data Source: The Maternity Experiences Survey, a population-based survey of a weighted sample of 76,508 women who were an average of 7 months post partum.
Disclosures: Dr. O'Campo and Dr. Janssen reported having no relevant conflicts of interest.
SEATTLE — Abuse is prevalent in the period surrounding pregnancy and is associated with a higher rate of postpartum depression, new data show. But certain factors might help identify abused women who are at highest risk and might benefit from targeted intervention.
In a national survey of Canadian women who had had a recent birth, 11% reported abuse in the past 2 years, according to study results presented at the meeting. Abused women were roughly three times more likely than their nonabused counterparts to have postpartum depression. Within the abused group, this risk was more than doubled for teenagers and women aged at least 35 years, as well as for women who were depressed before pregnancy.
Prevalence of Abuse
Studies in recent decades have explored the issue of violence around the time of pregnancy, noted coinvestigator Patricia J. O'Campo, Ph.D. “Yet, despite that, we actually don't have good estimates of prevalence,” she said. Reasons include variation in the types of abuse captured, the time period and perpetrators assessed, and the women studied.
In the national, population-based Maternity Experiences Survey, Dr. O'Campo and her colleagues used census data to identify Canadian women with a singleton infant aged 5-14 months. A random sample was selected for a computer-assisted telephone interview that asked whether they had experienced any of 10 types of abuse (actual or threatened) in the past 2 years, as well as questions from the EPDS (Edinburgh Postnatal Depression Scale).
Interviews were conducted with 6,421 women, who represented a weighted sample of 76,508 women, according to Dr. O'Campo, an epidemiologist at the University of Toronto. Most were 5-9 months post partum (average, 7.3 months).
Fully 11% of the women reported experiencing abuse in the past 2 years. In stratified analyses, the prevalence was highest among teenagers (40%); women with an annual income less than $20,000 (28%); aboriginal women (30%); and nonmarried, noncohabiting women (35%). By far, the leading perpetrators were partners (reported by 6% overall), followed by family members (2%), strangers/others (2%), and friends (1%).
Abused women most often said they had been pushed, grabbed, or shoved; were threatened with being hit; or had something thrown at them, noted Dr. O'Campo. And they most commonly reported that just one incident of abuse had occurred, and that the abuse had taken place only before pregnancy. The patterns of abuse type, timing, and perpetrator were generally the same among low-income and nonmarried subgroups. But those two subgroups differed with respect to the frequency of abuse, more commonly reporting two to five incidents or six or more.
“The 11%, I think, is significant,” she said, adding that previous population-based studies have found prevalences of less than 5% for 1-year periods. “But I think it could be higher, actually, if we had had a full spectrum of abuse items that were asked about,” such as control and restriction, she added. The diverse nature of perpetrators suggests that future research should not focus solely on partners, according to Dr. O'Campo.
“Contrary to common perception,” abuse is not necessarily a high risk around the time of pregnancy; “in fact, it's lower than, say, the abuse that was experienced before pregnancy,” she observed. “It would be important for future studies to be able to ask questions so that we know more about why abuse might decline during pregnancy,” she said. For example, “is it because the pregnancy is disclosed and known, and that tends to be protective, or that partners change?”
Predictors of Postpartum Depression
“Exposure to family violence is increasingly understood to be an important risk factor for adverse pregnancy outcomes,” said coinvestigator Patricia A. Janssen, Ph.D. “But its role in the development of postpartum depression has not been well studied yet.”
Certain psychosocial factors have been linked to the risk of family violence and postpartum depression, questioning the relationship between the two, she added.
Overall, 8% of the women in the survey screened positive for postpartum depression (defined as an EPDS score of at least 13 of 30), reported Dr. Janssen, an epidemiologist at the University of British Columbia in Vancouver. The rate was nearly threefold higher among abused women (17%) than among their nonabused counterparts (6%).