A curious species of barnacle (Loxothylacus panopaei) attaches itself to crabs, hijacking their reproductive organs and forcing them to bear barnacle larvae (male crabs are not immune). The parasites affect things such as the crab’s immune system and molting cycles as the larvae reproduce.
Things like sex, sexuality, and reproductive rights are hotbed topics. There are hosts of ethical dilemmas and questions that we can think of if a similar phenomenon were applied to human hosts.
In Octavia Butler’s Bloodchild, even human males can become a “mother” to alien lifeforms. They may, for whatever reason, actually prefer human hosts and turned us into a race of brood mares. What if a male was forced to reproduce or perform functions ordinarily assigned to another gender? What if a species would go extinct without a host? What if a human wanted to be the mother of an alien, and (if properly compensated) was able to turn it into a lucrative arrangement.