Producer Frank Mancuso Jr. wanted the creatures to look slightly different from H.R. Giger's original concept. He did not contribute to the designs in this film and the creatures were redesigned by Rob Hinderstein.
Executive Producer Frank Mancuso Jr. wanted this sequel to be aimed more at young adults so the characters were written to be younger than what was originally planned.
A scene which was changed due to budgetary reasons had Sara scratch a campus student's cheek with her alien finger, which looked like a spike. Instead, this was changed to Sara throwing the man over her into a hedge in the final film.
Amelia Cooke said she and Sunny Mabrey started attending sci-fi conventions together after the film was released. They thought it was neat meeting people who cared about the movie, but Cooke said it was mostly "young guys with sweaty palms" starring at her and Mabrey and probably picturing them naked. It got creepy at times.
Both Sil and Sara's mother Eve were ectogens - persons who were, or are being, gestated in artificial wombs - whereas Sara is not; she gestated in Eve's womb.