Alcohol use during pregnancy is the direct cause of fetal alcohol syndrome (FAS). We aimed to estimate the prevalence of alcohol use during pregnancy and FAS in the general population and, by linking these two indicators, estimate the number of pregnant women that consumed alcohol during pregnancy per one case of FAS. We began by doing two independent comprehensive systematic literature searches using multiple electronic databases for original quantitative studies that reported the prevalence in the general population of the respective country of alcohol use during pregnancy published from Jan 1, 1984, to June 30, 2014, or the prevalence of FAS published from Nov 1, 1973, to June 30, 2015, in a peer-reviewed journal or scholarly report. Each study on the prevalence of alcohol use during pregnancy was critically appraised using a checklist for observational studies, and each study on the prevalence of FAS was critically appraised by use of a method specifically designed for systematic reviews addressing questions of prevalence. Studies on the prevalence of alcohol use during pregnancy and/or FAS were omitted if they used a sample population not generalisable to the general population of the respective country, reported a pooled estimate by combining several studies, or were published in iteration. Studies that excluded abstainers were also omitted for the prevalence of alcohol use during pregnancy. We then did country-specific random-effects meta-analyses to estimate the pooled prevalence of these indicators. For countries with one or no empirical studies, we predicted prevalence of alcohol use during pregnancy using fractional response regression modelling and prevalence of FAS using a quotient of the average number of women who consumed alcohol during pregnancy per one case of FAS. We used Monte Carlo simulations to derive confidence intervals for the country-specific point estimates of the prevalence of FAS. We estimated WHO regional and global averages of the prevalence of alcohol use during pregnancy and FAS, weighted by the number of livebirths per country. The review protocols for the prevalence of alcohol use during pregnancy (CRD42016033835) and FAS (CRD42016033837) are available on PROSPERO. Of 23 470 studies identified for the prevalence of alcohol use, 328 studies were retained for systematic review and meta-analysis; the search strategy for the prevalence of FAS yielded 11 110 studies, of which 62 were used in our analysis. The global prevalence of alcohol use during pregnancy was estimated to be 9·8% (95% CI 8·9-11·1) and the estimated prevalence of FAS in the general population was 14·6 per 10 000 people (95% CI 9·4-23·3). We also estimated that one in every 67 women who consumed alcohol during pregnancy would deliver a child with FAS, which translates to about 119 000 children born with FAS in the world every year. Alcohol use during pregnancy is common in many countries and as such, FAS is a relatively prevalent alcohol-related birth defect. More effective prevention strategies targeting alcohol use during pregnancy and surveillance of FAS are urgently needed. Centre for Addiction and Mental Health (no external funding was sought).

Alcohol consumption during pregnancy may cause a wide range of adverse health effects to the developing fetus, including but not limited to cognitive, behavioral, emotional, and adaptive functioning deficits, as well as congenital anomalies. The health effects of prenatal exposure to ethyl alcohol have been subsumed under the umbrella term fetal alcohol spectrum disorder (FASD), which consists of as many as 4 diagnostic entities, including fetal alcohol syndrome (FAS), partial FAS, alcohol-related neurodevelopmental disorder, and depending on the diagnostic guideline, alcohol-related birth defects.^1-3 Alcohol can affect any organ or system in the developing fetus, and as such, individuals with FASD may experience a broad array of comorbid conditions. A recent study identified 428 comorbid conditions in individuals with FASD, with diagnoses from 18 of 22 chapters of the International Statistical Classification of Diseases and Related Health Problems, 10th Revision (ICD-10).⁴ Thus, clinicians from all specialties and other health service professionals will likely encounter cases of FASD. The effects of prenatal alcohol exposure have lifelong implications, and thus, FASD is costly for society.^5,6 For example, the lifetime cost for a person with FASD in North America is estimated at more than $1 million.^7,8

Smoking during pregnancy has been linked to numerous adverse health consequences for both the developing fetus and mother. We estimated the prevalence of smoking during pregnancy by country, WHO region, and globally and the proportion of pregnant women who smoked during pregnancy, by frequency and quantity, on a global level. For this systematic review and meta-analysis, we did a comprehensive systematic literature search for studies reporting the prevalence of smoking during pregnancy in the general population, published between Jan 1, 1985 and Feb 1, 2016, using several electronic bibliographic databases (CINAHL, Embase, ERIC, Medline, Medline in process, PsychINFO, Scopus, and Web of Science), without language or geographical restrictions. We included original research studies published in a peer-reviewed journal and assessed study quality using a tool specifically developed for use in systematic reviews addressing questions of prevalence. Studies were excluded if they did not include lifetime non-smokers in their sample or estimate, used a sample not generalisable to the general population of the respective country, or did not provide primary data. To estimate the prevalence by country, we did country-specific random-effects meta-analyses for countries with two or more available empirical studies, and we predicted the prevalence using a multilevel fractional response regression model with country-specific indicators for countries with one or no study. We estimated the proportion of female daily smokers who do not quit once pregnant by calculating the regional and global averages of the prevalence of daily smoking during pregnancy and of the prevalence of daily smoking in women. To estimate the global prevalence, by frequency and quantity, we did random-effects meta-analyses using available data from all countries and applied the respective proportions to the global prevalence estimate. We did a time-trend analysis using a univariate multilevel fractional response model. The review protocol is available on PROSPERO, registration number CRD42017075837. Of 21 329 studies identified, 295 were retained for data extraction. We calculated estimates via meta-analysis for 43 countries and via statistical modelling for 131 countries. The three countries with the highest estimated prevalence of smoking during pregnancy were Ireland (38·4%, 95% CI 25·4-52·4), Uruguay (29·7%, 16·6-44·8), and Bulgaria (29·4%, 26·6-32·2). The global prevalence of smoking during pregnancy was estimated to be 1·7% (95% CI 0·0-4·5). The prevalence of smoking during pregnancy was 8·1% (95% CI 4·0-12·2) in the European Region, 5·9% (3·2-8·6) in the Region of the Americas, 1·2% (0·7-1·7) in the Southeast Asian Region, 1·2% (0·0-3·7) in the Western Pacific Region, 0·9% (0·0-1·9) in the Eastern Mediterranean Region, and 0·8% (0·0-2·2) in the African Region. Globally, 72·5% (95% CI 70·4-75·0) of pregnant women who smoked were daily smokers, and 27·5% (25·4-29·6) of them were occasional smokers; 51·8% (95% CI 50·0-53·5) women who smoked were light smokers, 34·8% (33·1-36·4) were moderate smokers, and 13·5% (12·3-14·7) were heavy smokers. Furthermore, the proportion of women who smoked daily and continued to smoke daily during pregnancy was 52·9% (95% CI 45·6-60·3), ranging from 30·6% (95% CI 25·6-36·4) in the European Region to 79·6% (44·2-100·0) in the Western Pacific Region. Smoking during pregnancy is still a prevalent behaviour in many countries. These findings should inform smoking prevention programmes and health promotion strategies, as well as draw attention to the need for improved access to smoking cessation programmes for pregnant women. Centre for Addiction and Mental Health.

In 2004, tuberculosis (TB) was responsible for 2.5% of global mortality (among men 3.1%; among women 1.8%) and 2.2% of global burden of disease (men 2.7%; women 1.7%). The present work portrays accumulated evidence on the association between alcohol consumption and TB with the aim to clarify the nature of the relationship. A systematic review of existing scientific data on the association between alcohol consumption and TB, and on studies relevant for clarification of causality was undertaken. There is a strong association between heavy alcohol use/alcohol use disorders (AUD) and TB. A meta-analysis on the risk of TB for these factors yielded a pooled relative risk of 2.94 (95% CI: 1.89-4.59). Numerous studies show pathogenic impact of alcohol on the immune system causing susceptibility to TB among heavy drinkers. In addition, there are potential social pathways linking AUD and TB. Heavy alcohol use strongly influences both the incidence and the outcome of the disease and was found to be linked to altered pharmacokinetics of medicines used in treatment of TB, social marginalization and drift, higher rate of re-infection, higher rate of treatment defaults and development of drug-resistant forms of TB. Based on the available data, about 10% of the TB cases globally were estimated to be attributable to alcohol. The epidemiological and other evidence presented indicates that heavy alcohol use/AUD constitute a risk factor for incidence and re-infection of TB. Consequences for prevention and clinical interventions are discussed.