Immigrant  and Aboriginal  women may be regarded as vulnerable populations since challenges exist with respect to access and navigation of health services and more specifically maternity care services. Difficulties may be encountered in terms of accessing culturally appropriate care in addition to other challenges such as language barriers and discriminatory policy and practices. Without culturally appropriate health care delivery a negative trajectory of events may occur that range from simple miscommunication to life-threatening incidents [1, 3]. The danger is especially severe during the perinatal period, which is for women and their children a vulnerable life stage and a sensitive period of interaction with the Canadian health care system . Public health initiatives increasingly require healthcare organizations to promote, protect and contribute to reducing health inequities.
Diversity and Health of Immigrants and Aboriginal Peoples in Canada
For this research, we utilize the Canadian Council of Refugees definition of an immigrant: a person who has settled permanently in another country. Immigrant women are a tremendously diverse group that includes economic skilled workers, refugees and asylum seekers, temporary foreign workers, and those without legal status . Canada as a multicultural society has a long standing history of embracing diverse immigrant groups because of the strategy of utilizing immigration as a means of population expansion and nation building . While the majority of immigrants during the first 70 years of the 20th century were of European origin, over the past 30 years there has been a shift with larger groups of immigrants arriving from Asia and the Middle East, the Caribbean and Central America, Africa, Oceania and other countries . A recent report from Statistics Canada predicts that members of visible minority groups will comprise between 29% and 32% of Canada's population in 2031 .
As evidenced by the healthy immigrant effect [9, 10] relatively healthy immigrants enter Canada, yet within 10 years a convergence is observed in terms of health status moving towards the Canadian average. A number of explanations are postulated for this, including health selection, acculturation and the stress of relocation that may erode health advantage , and distrust of Western medicine with a preference for seeking out traditional health care providers. It is important to note that the healthy immigrant effect largely affects those communities whose immigration is planned, since populations who relocate as refugees or asylum seekers are found to have compromised health status, with women often having been traumatized by war, rape and the transgression of their human rights . Many may have lived in refugee camps for several years prior to immigration; therefore the pre-migration period may exert a powerful influence on health status including those related to maternal health and maternity service provision.
Aboriginal peoples is a collective name for all original peoples of Canada and their descendants, and the Constitution Act of 1982 specifies that the Aboriginal peoples in Canada consist of three groups: First Nations, Inuit and Métis . Aboriginal peoples are the fastest growing population in Canada. Between 1996 and 2006, the population grew by 45 percent, almost six times faster than the non-Aboriginal population growth rate of 8 percent . Aboriginal peoples in Canada are a vastly diverse population. For instance, Canada's First Nations peoples consist of more than 600 different communities, under approximately 50 different linguistically and culturally distinct groups . The effects of colonization and policies associated with the Indian Act have had enormous consequences on Aboriginal peoples' health and well-being that continues to this day.
Numerous health inequities exist for Aboriginal people, which are directly and indirectly related to the social, economic, cultural, and political factors that result in a disproportionate burden of ill health at both the individual and the community level [15, 16]. These health challenges and their determinants have largely been maintained by an intergenerational cycle of cumulative effects/trauma (often leading to 'normalized' patterns of ill-health and abuse) which helps explain how a disproportionate number of Aboriginal people experience social and health challenges compared to the general population .
Maternal and Birth Outcomes of Immigrant and Aboriginal Women: Relevance of Food Choices and Practices
Largely epidemiological research from Canada and elsewhere has reported equal or more favourable birth outcomes for migrants [18–21] supporting an "epidemiological paradox" associated with the concept of the "healthy migrant effect". Numerous other reports highlight serious problems of equity in perinatal health outcomes [22–24] particularly for refugees  and other immigrants after increased lengths of stay (with the accompanying acculturation) [26, 27]. A recent Canadian study found higher rates of low birthweight and full-term low birthweight (i.e., small for gestational age or SGA) for infants born to recent immigrant women  and immigrants living throughout Europe have been reported to be at substantial risk for pre-term delivery (24%), for perinatal mortality (50%), and for congenital malformations (61%) . The hospital costs for preterm and SGA newborns are higher than those for their normal-growth counterparts by 9 and 2 times, respectively .
Aboriginal people experience a disproportionate burden of ill-health compared with the rest of the Canadian population [16, 29] including such indices such as maternal and infant mortality [30, 31]. Poorer birth outcomes including stillbirths, low birthweight infants and prematurity are often reported . There is conflicting evidence to support Aboriginality itself to be the predisposing factor, multiple issues related to socioeconomic status in addition to medical and prenatal care also likely play a role .
While considerations of infant mortality and birth weight are important, these outcomes are not adequate or all-encompassing measures for evaluating maternal and infant health and well-being over their lifetimes. Aboriginal women have a greater chance to have gestational diabetes with the risk of giving birth to high birth-weight babies (> 4 kg, also known as macrosomia) [34, 35]. Negative maternal characteristics and birth outcomes of immigrants include significantly higher rates of gestational diabetes (predisposing the mothers to preeclampsia and type 2 diabetes and their offspring to obesity and type 2 diabetes) ; dieting with low maternal weight gain (compromising both newborn and maternal health) ; genetic anomalies such as neural tube defects due to lack of folic acid intake ; and maternal anemia (increasing the risk of preterm delivery) . All of these outcomes relate to food choices and practices.
Indeed investigators have documented changes in the everyday diet of immigrant women towards more processed foods and animal proteins as well as foods high in fat, salt, or sugar [38, 39]. Evidence suggests an increasing prevalence of obesity post-migration because of the adoption of a Western diet  likely due to "obesogenic" food environments in the vicinities of many immigrants residences . Conversely, immigrant women may instead internalize the dominant body norms of their settlement home (i.e., the skinny model or actress common in media images in North America, Australia, and Europe) and reduce their dietary intake, even during reproduction, to maintain or quickly return to these hegemonic body ideals . The first author currently leads a project investigating maternity care experiences of immigrant and minority women which involves interviews with immigrant women, policy-makers, immigrant support agency representatives, and health care professionals in the cities of Edmonton and Brooks, representing both urban and rural regions of the province of Alberta, Canada. The analysis of data elicited in Edmonton has revealed two topics of significance for the maternal health of Canadian marginalized women: nutrition during the perinatal period, and psychological health and well-being in the post-natal period (unpublished data).
Aboriginal women living off-reserve in Canada are also likely affected by the urban obesogenic food environments. Relying on data from the 2004 Canadian Community Health Survey, a greater proportion of the diets of Aboriginal women living off-reserve, compared to non-Aboriginal women, consisted of snack foods including soft drinks (considered Other Foods by the Canada Food Guide to Healthy Eating of 1992) .
Successfully providing appropriate prenatal nutritional and diet education requires the legitimization and incorporation of the pervasive traditional beliefs and practices of immigrant women, which they often adhere to despite their new milieu [44, 45]. Moreover, research and care related to pregnancy and parenthood for Aboriginal women needs to be based on the priorities and experiences of Aboriginal women and "turning around" the intergenerational impacts of residential schooling and colonialization .
Maternity care nurses may face considerable challenges in conveying information to immigrant and Aboriginal women regarding the optimum food choices for pregnancy because of language difficulties and ethnocultural differences in reproductive health and food practices. Research is needed to elicit understanding of ethnocultural food choices and practices and to improve culturally based competency of maternity care. The development of nutrition education materials tailored to immigrant and Aboriginal populations and the provision of related education targeted to maternal care providers together have great potential to positively impact maternal and childhood health and well-being; both the transmission of appropriate messages on nutrition and the enhancement of accessibility and acceptability of maternal health care will contribute to these positive effects.
The aim of this project is to understand ethnocultural food and health practices and how these intersect in a particular social context of cultural adaptation and adjustment. An end product of this research will be a visual tool for each of three participating ethnocultural groups (Aboriginal, Chinese and Sudanese), that maternity nurses can use during health promotion interactions to convey the elements of an optimal nutritional diet. The tools will be graphic and pictorial and will enable women with limited English language skills or literacy levels to elicit pertinent information. Our ultimate goal is to improve the care-giving capacities of health practitioners (particularly maternity nurses in this study) working in a multicultural perinatal clinic setting. Our research question is How do health beliefs and practices during reproduction (i.e. preconception, during pregnancy, labour and birth, and postnatal period) of immigrant and Aboriginal women affect their food choices and subsequent health status?