Migration and health behaviour during pregnancy
Authors: Krista M Perreira
Journal: BMJ (2008)

The accompanying prospective national cohort study by Hawkins and colleagues adds to the literature on acculturation (the social and psychological exchanges that take place when different cultural groups interact), health disparities, and the use of alcohol and tobacco during pregnancy.1 It finds that after women immigrate to England, their maternal health behaviours worsen as their length of residency increases.

Smoking and alcohol consumption during pregnancy are common in the United States and Europe and are important preventable causes of maternal morbidity during pregnancy, poor fetal development, and poor infant health.1 2 As smoking and alcohol consumption increase in developing countries, such as those in South East Asia and the Western Pacific region,3 4 taboos against these behaviours in women weaken, and more women are at risk of smoking and drinking alcohol during pregnancy.

The World Health Organization predicts that 20% of all women will smoke by 2025, up from 12% in 2005. Although similar worldwide data on trends are not available for alcohol use by sex, a proportional rise in consumption of alcohol in women of childbearing age can be expected. Overall, these increases in tobacco and alcohol use are worrying because they may lead to a rise in alcohol and tobacco related problems during pregnancy.

As the number of international migrants continues to increase worldwide, smoking and alcohol consumption patterns among women in developing countries will have consequences for medical providers throughout Europe and North America. In 2005, 9% of the European population and 14% of the North American population were foreign born residents, primarily from Africa, Central and South America, or Asia.5 Moreover, many new immigrants to European and North American countries were women (53% and 50%).5 Therefore, it is increasingly important that medical and public health professionals in Europe and North America understand the maternal health behaviours of these growing segments of their populations and how they differ from majority white populations.

Women who migrate from developing regions of the world to more economically developed countries bring with them the health beliefs, traditions, and cultural practices of their home countries. Thus, not surprisingly, research on migration and maternal health has found that foreign born women who move to Europe or the US from developing countries with historically lower levels of smoking and alcohol consumption continue to be less likely to smoke and drink after migration. With more time in their new host country, however, greater access to alcohol and tobacco and fewer normative restrictions on the use of these substances result in an increase in these women’s use of alcohol and tobacco during pregnancy. Second generation children of immigrants have rates of smoking and alcohol consumption during pregnancy more similar to those of majority white populations in their communities. As they acculturate, other aspects of maternal health behaviours (such as breastfeeding and diet) also worsen and come to resemble those of the majority white population in their communities.6 7

A variety of explanations for the transformation of maternal health behaviours over time and across generations have been offered.2 7 8 Firstly, increasing socioeconomic wellbeing can make alcohol and tobacco more affordable for immigrants. Secondly, minority populations in the US and elsewhere tend to live in urban areas where advertisers and retail outlets that promote alcohol and tobacco are concentrated. Thus, they and their children may be increasingly exposed to messages that encourage the use of these substances. Thirdly, over time, immigrants and their children may move out of immigrant minority communities with close ties to their homelands and strong, informal community supports for traditional health beliefs and practices, including norms that discourage smoking and alcohol consumption. Fourthly, increasing use of alcohol and tobacco by first and second generation immigrant men may increase their use in women. Support for reducing smoking and alcohol consumption during pregnancy, especially from a cohabitating partner, can be essential.2 9 If her partner smokes or drinks, a woman is continually inundated with social and psychological queues that can trigger the desire to use these substances. 

Despite its importance for designing prevention and intervention programmes that promote health behaviours during pregnancy, researchers have only just begun to evaluate what factors explain the changes in maternal health behaviour that occur after migration. Moreover, intervention studies have typically concentrated on middle class, white, non-Hispanic women.10 Nevertheless, results from one recent intervention study conducted with ethnic minorities in the US suggest that a brief 10-15 minute counselling session with a trained health educator can decrease alcohol consumption.10 Similarly, recent studies of smoking cessation during pregnancy suggest that interventions that include a mother’s partner, encourage smoking restrictions in the home, and include brief counselling or education components that highlight the negative aspects of smoking promote its reduction during pregnancy.9 11

Future research on health disparities, migration, and substance use should investigate differences in risk and protective factors in relation to nativity and race-ethnicity. In addition, more attention should be paid to conditions—especially depression and domestic violence—that co-occur with maternal substance use. In the US, 20% of women who were using alcohol, tobacco, or illicit drugs one year after delivery had symptoms of depression or anxiety and 32% had experienced domestic violence.12 The co-occurrence of these conditions may be even higher among immigrant women. The research by Hawkins and colleagues is an important first step in developing programmes and policies that promote the health of immigrant women and their children.