Complex cytokine networks play an important role in a wide range of reproductive and pregnancy related processes. Here, we review the current knowledge concerning the impact of cytokines on uterine physiology and pathophysiology. Cytokines influence a range of uterine functions during the menstrual cycle, implantation, pregnancy and labour. The synergistic interactions between individual cytokines are intricate and dynamic, and modulated by pregnancy hormones. It is not surprising therefore, that perturbations to cytokine signalling are associated with adverse pregnancy outcomes, such as miscarriage, pre-eclampsia, preterm labour and foetal brain injury. Further insight into the complexity of cytokine networks will be required to develop novel therapeutic strategies for the treatment of cytokine imbalances in pregnancy.