Wilding S, Ziauddeen N, Roderick P, et al. - Through a population-based birth cohort using routine antenatal healthcare data of 65,909 singleton live births born to mothers aged ≥ 18 years between 24-week and 42-week gestation at University Hospital Southampton, UK, between 2004 and 2016, the researchers examined socioeconomic disparities, using maternal educational attainment, maternal and partner employment status, and lone motherhood indicators, in the risk of small-for-gestational-age (SGA) births, their time trend, potential mediation by maternal smoking and body mass index, and impact modification by parity. Bigger risk of being SGA was observed in babies born to mothers educated up to secondary school level, who were unemployed or with unemployed partners. As estimated by linear interactions with the year of birth, no statistically important alteration in the magnitude of this risk variation by these indicators over time between 2004 and 2016 was found. In comparison with partnered mothers, babies born to lone mothers were not at greater risk, when adjusted for maternal smoking. In multiparous vs primiparous women, the inverse correlation between maternal educational attainment and SGA risk seemed greater, and the opposite was accurate for maternal and partner’s unemployment where the relationship was more powerful in primiparous women. Hence, with variations in correlation strength by parity, socioeconomic disparities in SGA risk by educational attainment and employment status were not narrowing over time. In lone mothers, the greater SGA risk was potentially defined by maternal smoking. Moreover, to decrease SGA risk, preventive interventions should target socially disadvantaged females, including preconception and postpartum smoking cessation.