Fertility decline in Aedes aegypti mosquitoes is associated with reduced maternal transcript deposition and does not depend on female age

<p>Female mosquitoes undergo multiple rounds of reproduction known as gonotrophic cycles. A gonotrophic cycle spans the period from blood meal intake to egg laying. Nutrients from vertebrate host blood are necessary for completing egg development. During oogenesis, a female pre-packages mRNA into her oocytes, and these maternal transcripts drive the first two hours of embryonic development before zygotic genome activation. In this study, we profiled transcriptional changes in 1-2 hour-old <em>Aedes aegypti</em> embryos across two gonotrophic cycles. We found that homeotic genes which are regulators of embryogenesis are downregulated in embryos from the second gonotrophic cycle. Interestingly, embryos produced by <em>Ae. aegypti</em> females progressively reduced their ability to hatch as the number of gonotrophic cycles increased. We show that this fertility decline is due to increased reproductive output and not the mosquitoes' age. Moreover, we found a similar decline in fertility and fecundity across three gonotrophic cycles in <em>Ae. albopictus</em>. Our results are useful for predicting mosquito population dynamics to inform vector control efforts.</p>