Atopic disease has been on the rise in the United States and worldwide. Speculation is that the immune system plays a role in its development in utero. The purpose of this review is to evaluate the strength of available evidence supporting or refuting the impact of maternal long-chain omega-3 status on atopy development in offspring. After reviewing 21 primary articles, the evidence shows a potential for omega-3 fatty acids to influence immune system development in utero and subsequent atopy in offspring. More randomized controlled trials are needed to confirm these findings, with attention to the confounding variables.