Malaria Infection Suppresses Proestrus and Estrus While Prolonging Diestrus in Mice
DOI:
https://doi.org/10.51412/psnnjp.2026.009Keywords:
Malaria, Plasmodium berghei, estrus cycle, reproductive health, inflammationAbstract
Background: Malaria remains a significant global health concern. Beyond its well-known pathogenesis and effects, the impact of malaria on female reproductive health, particularly estrous cycle dynamics, is poorly understood. This study investigated the influence of Plasmodium berghei (NK65 strain) infection on estrus cycle phases in female Swiss mice.
Methods: Eighteen female Swiss mice (8–12 weeks old) were assigned to control (uninfected) and infected (P. berghei NK65 strain) groups (9 per group). Estrus cycles were monitored through daily vaginal cytology for 30 days (15 days pre-inoculation and 15 days post-inoculation). The number of days spent in each estrus phase (proestrus, estrus, metestrus, and diestrus) was recorded for each group. The differences before and after inoculation in the two groups were analyzed using a Chi Squared test for proportions, with statistical significance set at a Pvalue less that 0.05 (two-sided).
Results: Parasitemia in infected mice reached an average of 24% by Day 14, confirming successful infection. Control mice maintained normal estrus cycles, with no significant post-inoculation disruptions. However, infected mice exhibited severe estrus cycle disturbances, including suppression of proestrus and estrus phases post-inoculation (p < 0.05) and a significant increase in diestrus duration (p < 0.05).
Conclusion: Plasmodium berghei infection significantly disrupted estrus cycle dynamics in female mice, primarily suppressing the reproductive phases essential for ovulation while prolonging diestrus. These findings underscore the potential impact of malaria on female reproductive health. Further research is needed to elucidate the underlying mechanisms driving these disruptions.
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