The Developmental origins of human adult diseases (DOHAD) has initially emphasised the effects of maternal undernutrition during foetal development on long-term outcomes in the adult offspring, including effects on fertility. More recent work has provided evidence that preconceptional nutritional conditions and periconceptional environment also play a major role in programming the offspring susceptibility to disease. Epigenetic mechanisms, which may be mediated by macro- and micro-nutriments, endocrine status and oxidative stress, are the focus of the mechanistic studies aimed at understanding the processes involved in these effects. This article details available data in the area, using examples from numerous animal studies.