 Paraproxifen, PPF, is an insect growth regulator used in the co-treatment of long-lasting insecticidal nets for its ability to sterilize female mosquitoes. Most studies observe oviposition rates in the laboratory to evaluate the efficacy of PPF-treated nets. However, this method has several technical limitations. In our study, we evaluated the effectiveness of PPF-treated nets using two methods, observing oviposition rates in cylinder assays and dissecting blood-fed females to determine their exposure status. Both techniques showed high sensitivity in detecting PPF-exposed mosquitoes, but only dissection had high specificity in identifying non-exposed mosquitoes. Additionally, we found that dissection could be used to identify PPF-exposed mosquitoes in nets treated with a pyrethroid or co-treated with a pyrethroid and PPF in tunnel tests. Finally, we demonstrate that dissection is a reliable technique to assess sterility in female anopheles gambi mosquitoes and can be used as a predictor of PPF exposure. This article was authored by Alina Soto, Mark Rowland, Louisa A. Messenger and others. We are article.tv, links in the description below.