Pyriproxyfen does not cause microcephaly or malformations in a preclinical mammalian model.

Pyriproxyfen is used in Brazil to combat epidemics of Dengue Fever, Chikungunya Fever, and Zika virus. This study assessed the effects of pyriproxyfen on reproductive performance, embryo-fetal development, head measurements, and DNA integrity in a preclinical model. Thirty pregnant mice were divided into three groups (n = 10): control (drinking water-0.1 ml/10 g (body weight-b.w., gavage) and treated with pyriproxyfen 0.0002 mg/kg and 0.0021 mg/kg (b.w., gavage) during the gestational period. Analysis of biometric, reproductive performance and embryo-fetal development parameters related to control presented no significant differences, suggesting no maternal or embryo-fetal toxicity. Head measurements showed no differences except an increase in anterior/posterior measurement and glabella/external occipital protuberance. Analysis of DNA integrity showed an increase in micronucleus only at 72 h for the lowest dose group. Thus, we infer that pyriproxyfen is not related to the occurrence of microcephaly, nor does it alter reproductive performance, embryo-fetal development or DNA integrity.