Since the pregnancy period was 18 days in mice that were infected with PbNK65L on day 12 post-mating, the risk of preterm delivery appears to increase from day 6 p.i. Several studies reported that production of pro-inflammatory cytokines, such as IFN-γ and TNF-α, was enhanced in placenta from pregnant women or mice infected with malaria parasites [15–19, 30, 31]. This evidence concerns the gene TNF and malaria.