Our findings suggest a persistent adverse effect over time for children’s mental health related to prenatal exposure to ≥4 drinks in a single day. This pattern of drinking on one or more days during pregnancy carries risk in the absence of daily drinking. The pattern of findings at age 11 years was similar to our earlier findings following up this cohort up till age 7. The persistence of adverse effects into mid-childhood, even with small individual effect sizes, is significant at a whole-population level. Clinicians should enquire about episodic binge drinking as well as regular drinking when taking a history of pregnancy and keep this in mind when assessing mental health and learning problems [15, 18, 27, 28]. At an individual level, pregnant women should be aware of possible risks associated with episodic binge-pattern drinking, even if this occurs on an occasional basis. Our findings have implications for clear policy messages about patterns of alcohol consumption during pregnancy, whereby women who choose to drink occasionally should avoid having several drinks in a day.
