In the initial cut of Alien, the alien possessed a complete life cycle, with the still-living bodies of its victims converted into eggs. However, the scene showing this final stage was cut for reasons of pacing, leaving the ultimate origin of the eggs obscure. This allowed Aliens director James Cameron to introduce a concept he had initially conceived for a spec script called Mother, a massive mother alien which laid the eggs and formed the basis for the aliens' life cycle. Cameron conceived the Queen as a monstrous analogue to Ripley's own maternal role in the film. In that vein, some critics have compared it to
Grendel's mother.
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The eggs laid by the queen are large, ellipsoidal leathery objects about one meter high with a four-lobed opening at the top. As a potential host approaches, the egg's lobes unfold like flower petals, and the parasitic facehugger explodes from within.
Giger initially designed the eggs with a much more obviously vaginal appearance, complete with an "inner and outer vulva". The producers complained that Catholic countries would ban the film if the allusion was too strong, so Giger doubled the lobes to four, so that, in his words, "seen from above, they would form the cross that people in Catholic countries are so fond of looking at."