normal aliens dont reproduce like humans
predaliens dont reproduce like preds
end of story
explain whatever way u want, for me its a young queen ability to get protection to start egg laying, why does it stop doing it? burster coem from isnide predalien, when its out of bursters theres no more, speculate about everything that suffers culateral damage, im sure u guys will find a way
or maybe egg laying is only once theres no more hosts, to assure species continuity, but it dont make sense with aliens at all.....