Maternal alcohol intake up to and during pregnancy and risk of adverse birth outcomes: evidence from a British cohort

• Published in: The Lancet (British edition) 2013-11, Vol.382 (S3), p.S79-S79
• Main Authors: Nykjaer, Camilla, MSc, Alwan, Nisreen A, MFPH, Greenwood, Darren C, PhD, Simpson, Nigel A B, MBBS, Hay, Alastair W M, Prof, White, Kay L M, MSc, Cade, Janet E, Prof
• Format: Article
• Language: English
• Subjects: adulthood; alcohol drinking; Alcoholic beverages; Alcohols; biomarkers; Birth weight; Caffeine; Cardiovascular diseases; cotinine; education; energy intake; ethics; fetal development; gestational age; guidelines; infants; Internal Medicine; nationalities and ethnic groups; noninsulin-dependent diabetes mellitus; odds ratio; planning; Pregnancy; pregnancy complications; pregnant women; premature birth; prospective studies; questionnaires; regression analysis; Reproductive health; Research ethics; risk; small for gestational age
• ISSN: 0140-6736; 1474-547X
• DOI: 10.1016/S0140-6736(13)62504-0

Abstract Background High maternal alcohol consumption has been linked to adverse birth outcomes such as small for gestational age and preterm birth, which in turn have been linked to increased risk of development of cardiovascular diseases and type 2 diabetes in adulthood. The UK Department of Health (DH) recommends that pregnant women and those trying to conceive should avoid alcohol and never drink more than 1–2 units once or twice a week. This study aimed to investigate the association between alcohol intake before and during different stages of pregnancy with both birthweight and gestational age. Methods Data were used from the Caffeine and Reproductive Health Study (CARE), a prospective birth cohort that included 1303 low-risk pregnant women aged 18–45 years, recruited from September, 2003, to June, 2006. Questionnaires administered in the first and second trimester and postpartum assessed alcohol consumption before pregnancy and for the three trimesters. Frequency of weekly alcohol consumption was analysed by categories of intake to accord with DH guidelines (≤2 units per week, >2 units per week, and a non-drinking category as the referent) and was related to preterm birth and size at birth, measured as grams and as customised birthweight centile, which takes into account maternal prepregnancy weight, height, parity, ethnicity, gestation, and baby's sex in multivariable linear and logistic regression models. We also adjusted for maternal age, caffeine intake, education, energy intake, and salivary cotinine as a biomarker of smoking status. Only participants with complete data for all variables were included in the analyses, which excluded just under 10% of the sample. All women provided informed consent and the study was approved by the Leeds West Local Research Ethics Committee (ref 03/054). Findings 1153, 1135, 793, and 377 women, respectively, had data available for birth outcomes and alcohol consumption before pregnancy and during the three trimesters. 74% of women before pregnancy and 53% in the first trimester reported alcohol intakes above the DH recommendation. For intakes above 2 units per week compared with non-drinkers, the adjusted differences in birth centile were −7·7 (95% CI −12·8 to −2·6; ptrend =0·009), −8·2 (−12·6 to −3·7; ptrend =0·002), and −6·4 (−11·8 to −1·1, ptrend =0·06) before pregnancy and during trimesters 1 and 2, respectively. The association with small for gestational age and preterm birth was strongest in trimester 1, w