Systematic review of effects of low–moderate prenatal alcohol exposure on pregnancy outcome

Abstract

Objective The aim of this study was to review systematically the available evidence on studies in humans on the effects of low-moderate levels of prenatal alcohol consumption (up to 10.4 UK units or 83 g/week) compared with consumption of no alcohol on pregnancy outcome.Design Systematic review.Population Pregnant women or women who are trying to become pregnant.Methods The search strategy included Medline, Embase, Cinahl and PsychInfo for the years 1970-2005. Titles and abstracts were read by two researchers and inclusion/exclusion being decided according to prespecified criteria. All the included articles were then obtained and read in full by the two researchers to decide on inclusion. The articles were assessed for quality using the Newcastle-Ottawa Quality Assessment Scales.Main outcome measures Outcomes considered were miscarriage, stillbirth, intrauterine growth restriction, prematurity, birthweight, small for gestational age at birth and birth defects including fetal alcohol syndrome.Results The search resulted in 3630 titles and abstracts, which were narrowed down to 46 relevant articles. At low-moderate levels of consumption, there were no consistently significant effects of alcohol on any of the outcomes considered. Many of the reported studies had methodological weaknesses.Conclusions This systematic review found no convincing evidence of adverse effects of prenatal alcohol exposure at low-moderate levels of exposure. However, weaknesses in the evidence preclude the conclusion that drinking at these levels during pregnancy is safe.Please cite this paper as: Henderson J, Gray R, Brocklehurst P. Systematic review of effects of low-moderate prenatal alcohol exposure on pregnancy outcome.

Changes in beverage consumption from pre-pregnancy to early pregnancy in the Norwegian Fit for Delivery study

“…At inclusion, in median gestational week 15 (range: [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20], the women answered an FFQ. The study design was cross-sectional as the women reported how often they consumed the different drinks at inclusion and in retrospect how often they drank the different beverages before they got pregnant.…”

“…Longitudinal studies on diet across the transition to motherhood find that women report changes both in beverage intake and drinking behaviour (14,15) . Much of the research on beverage consumption during pregnancy has focused on specific types of drinks (5)(6)(7)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27) or has been part of studies on nutrition during pregnancy (15,(28)(29)(30)(31)(32)(33) . Few, if any, studies have looked specifically at a broader range of beverage intake from pre-pregnancy to early pregnancy.…”

Commentary on Roerecke & Rehm (2012): The state of the science on moderate drinking and health—a case of heterogeneity in and heterogeneity out?

“…The plausibility of this alternative explanation is also made starkly apparent (although rarely remarked upon) by numerous studies reporting biologically implausible health benefits associated with moderate drinking [9]. Leading examples include the demonstration of significantly reduced risk of liver cirrhosis morbidity by moderate drinking males [10] and fewer birth complications for mothers who were light drinkers during their pregnancy [11]. There are also numerous other claims of health benefits from moderate drinking which should be scrutinized more closely, ranging from preventing ailments from dementia to the common cold.…”

Authors' response to: Different perspectives on the methodology of studying the potential effects of different alcohol drinking patterns in early pregnancy on the neuropsychological development of young children

“…Generally, our results seem to be well in line with previous findings. 12,13 Finally, a few general comments are made by the authors. First, Dr Garcia-Algar et al 2 state that, 'there is clear evidence from animal studies and from human clinical observation that prenatal exposure to alcohol has deleterious effects…'.…”