Pelo comentário do OP acima, esta história era " Friend to Man " de CM Kornbluth ; publicado originalmente em 10 Story Fantasy , Primavera de 1951, disponível no Internet Archive .
O insectóide é chamado de "screy", e a história termina de uma maneira consistente com sua descrição:
... Smith tried to move and could not. The itching in his back was a torment.
The screy mother did not look at the prostrate host as she turned and crawled up from the incubator to the surface. Something like fond humor wrinkled the surface of her thoughts as she remembered the little ones and their impatience. Heigh-ho! She had given them the best she could, letting many a smaller host go by until this fine, big host came her way.