INTRODUCTIONAlcohol is measured in units and "One unit is 10 ml or 8 g of pure alcohol" [1]. The maximum recommended intake of alcohol for women in the UK is 2-3 units/day; these have remained unchanged since 1995 when recommendations based on weekly quantities (units) were dropped in favour of daily quantities (units). The recommendations are comparable to international standards [2].The majority of adults in the UK report that they drink alcohol and for most adults, alcohol consumption is not considered to be health-damaging [3]. However, research has focused on the minority of the population whose patterns of consumption are associated with a range of health and social problems [4,5]. As a result, more is known about "risky" alcohol use than about the drinking patterns of the majority of the population. In contrast, this paper takes a population perspective that examines the underlying social determinants of alcohol use rather than focusing on a small proportion of "risky" drinking individuals in order to identify potential areas for widespread public health intervention [6].UK surveys provide important information on majority drinking patterns among women. They indicate that alcohol use is more common among white British women; women from minority ethnic groups are more likely to report never drinking or drinking less than once per week. They point, too, to positive gradients in the frequency, and negative gradients in the quantity, of alcohol use among socially advantaged groups [7][8][9][10]. Similarly, studies in other highincome countries report more frequent alcohol use among employed women with higher educational levels and living in higher income households [11,12]. The opposite has been found for drinking quantity. Women who are advantaged with respect to education, employment status, occupational class and household income consume smaller quantities of alcohol on drinking occasions than women from more disadvantaged backgrounds [11][12][13].Domestic circumstances are also associated with women's patterns of alcohol use. Compared with non-married women, married women report lower alcohol consumption in terms of both frequency and quantity [12]. Having children in the household is also associated with alcohol use, with decreased alcohol consumption among parents [4,12]. In addition, there AbstrAct Background: We examined patterns of alcohol use among mothers with infants in the UK focusing on (i) common ("majority") patterns of alcohol use (frequency and quantity) and (ii) associated social factors. Methods: We analyzed data from 15,510 mothers who took part in waves 1 and 2 of the millennium cohort study in 2000/1. Nine months after birth, mothers reported their frequency and quantity of alcohol use, along with information on social circumstances. Logistic regression, carried out in 2011, helped identify the social factors associated with majority patterns of alcohol use. Results: Majority patterns of alcohol use were: Infrequent drinking (never/<1/week), infrequent light drinking (1 unit/day, <1/we...