Research Update

Alcohol Use and Pregnancy: An Important Canadian Public Health and Social Issue

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1 Introduction

Women's use of alcohol during pregnancy is an important public health and social issue in Canada. This is due to the increasing societal awareness of the significant personal and social costs associated with fetal alcohol spectrum disorder (FASD). To help inform current discussions on what works best to respond to pregnant women's use of alcohol and related harms, this research update summarizes the Canadian and international (primarily US) literature. Three topics are reviewed: patterns of women's use of alcohol during pregnancy (sections 3 and 4); the characteristics of women who use alcohol during pregnancy and the circumstances surrounding their use (section 5); and the public health, social and legal responses to pregnant women's use of alcohol (sections 6 to 10). Within each topic, the strengths and limitations of the literature are reviewed, and from this, recommendations are made for further research. If applicable, programming and policy implications are discussed. The audience intended for this report is the various stakeholders of the Public Health Agency of Canada.

A large number of complex and interrelated factors help to explain the use of alcohol by women. This is particularly the case with drinking during pregnancy. Pregnant women's use of alcohol cannot be separated from other issues in their lives,¹ such as violence and socioeconomic status, and their alcohol use is often not easily isolated from other potentially harmful behaviours, including tobacco and other drug use. In general, problematic substance use for women is linked to a range of biological, genetic, psychological, social, cultural, relational, environmental, economic and spiritual factors.² However, there are good reasons to concentrate on alcohol alone. These range from the various negative health consequences of alcohol use for pregnant women, including physical, mental, emotional and spiritual well-being, to the fact that alcohol use during pregnancy is one of the leading causes of birth defects and developmental delays in Canadian children.³

Women who drink during pregnancy are at risk of having a child with an FASD, including its most visible presentation, fetal alcohol syndrome (FAS).^{i, 4,5} Estimating the number of children born in Canada with FASD and FAS is difficult.ⁱⁱ Among the key problems is that diagnostic capacity is inadequate and not evenly available across the country, studies are largely restricted to sub-populations that may not be representative, some research is methodologically weak, and there is a general lack of comparability among studies.⁶ FAS is estimated to occur at a rate of one to two per 1,000 live births, while FASD rates are less clear but undoubtedly higher.⁷ In Health Canada's Framework for Action on FASD, the incidence is estimated to be nine in 1,000 live births.⁸ With the recent publication of guidelines for diagnosing FASD, the calculated incidence will likely become increasingly accurate. It is also estimated that the incidence of FAS/FASD in some Aboriginal communities in Canada is higher.^9,10 Studies have suggested rates from 25 to 200 per 1,000 live births in some isolated northern communities.¹¹ There are no known studies that have researched FAS/FASD among other sub-populations of Canadians.¹²

Evidence is emerging, but still inconclusive, on the amount of alcohol, if any, women can safely use during pregnancy without affecting the fetus.^13-16 The amount,ⁱⁱⁱ timingiv and frequency^v of alcohol intake are critical factors in determining risk for FASD; however, other factors, including the mother's age, health, other substances used and the genetic susceptibility of the mother and of the fetus¹⁷ also help to determine outcomes. Recent research suggests that more moderate levels of drinking during pregnancy, in comparison to patterns of drinking that produce high levels of blood alcohol content, may cause longterm cognitive impairments.^{vi, 18-20} In the absence of conclusive information, Health Canada and other authorities, including the US Department of Health and Human Services,^21,22 recommend that women abstain from drinking alcohol during pregnancy.^vii Public health messaging similarly surrounds the adverse effects of alcohol on nursing infants (e.g. sleep–wake patterns, decreased milk intake, impaired motor development), and education about breastfeeding scheduling scheduling is promoted to ensure women that their babies will not be exposed to alcohol.^23-25

To support the health of pregnant women in Canada and to arrive at the most effective responses, it is important to understand the patterns of use among women drinking during pregnancy, the characteristics of these pregnant women, and the circumstances of their drinking. It is also equally important to be knowledgeable about current public health, social and legal responses to women's use of alcohol during pregnancy.

i. "Fetal Alcohol Spectrum Disorder (FASD) is an umbrella term describing the range of effects that can occur in an individual whose mother drank alcohol during pregnancy. These effects may include physical, mental, behavioural and learning disabilities with lifelong implications. The term FASD is not intended for use as a clinical diagnosis" (Chudley, A.E., J. Conry, J.L. Cook, C. Loock, T. Rosales, N. LeBlanc (2005). "Fetal alcohol spectrum disorder: Canadian guidelines for diagnosis". Canadian Medical Association Journal. 172 (5 suppl). pp. s1). "Fetal Alcohol Syndrome (FAS) is a medical diagnosis referring to a specific number of abnormalities associated with drinking alcohol during pregnancy. Fetal Alcohol Effects (FAE) is a term used to describe the presence of some, but not all, FAS characteristics when prenatal exposure to alcohol has been confirmed". (Health Canada (2001). The Facts: Fetal Alcohol Syndrome/Fetal; Alcohol Effects. ON: Health Canada. p. 1).

ii. It is important to acknowledge at the outset of this report that although alcohol use in pregnancy is necessary for the outcome of FASD, prevalence and incidence rates of the former cannot be equated with prevalence and incidence rates of the latter.

iii. An “unsafe” amount of alcohol consumption is commonly defined as 5 or more drinks on one occasion, or binge drinking. Some define it as 4 or more drinks on one occasion to account for women's slower metabolism rate compared with that of men's.

iv. Timing refers to the stage of pregnancy at which women drink. Alcohol-related damage to the fetus during the early stages of conception (first three weeks) can lead to miscarriage; up to 12 weeks, it can include abnormalities of the head and face, damage to the brain and lower birth weight; and at later stages, drinking can also cause developmental delays. Alberta Alcohol and Drug Abuse Commission: http://www.aadac.com/547_1222.asp.

v. An “unsafe” frequency of alcohol consumption is commonly defined as 7 or more drinks per week.

vi. A concern with studies that focus on moderate levels of alcohol consumption is that they frequently disregard the complexity of drinking behaviour and measure average levels of consumption. Abel commented that “[s]ince it is blood alcohol level, rather than the amount of alcohol consumed, this is critical for producing fetal damage; the difference in drinking patterns is a critical factor determining the potential dangers of alcohol” (Abel 1996). Moderate drinking during pregnancy. Clinica Chimica Acta, 246, 149–154). To illustrate, the calculation of an average level of consumption does not account for differences between two scenarios: woman A drank 2 alcoholic beverages on Friday evening and 5 on Saturday evening, and woman B drank 1 alcoholic beverage each night of the week with her dinner.

vii. There are national and international debates over appropriate public health messaging regarding drinking during pregnancy. See later prevention-specific sections of this report for more information.

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