This trope emphasizes the body as a vessel for forced reproduction and transformation. A host becomes pregnant through unnatural means: parasitic insemination, possession, or alien impregnation. The pregnancy progresses rapidly, with unsettling physical and emotional changes. The horror is rooted in loss of agency: the host cannot stop the process, and others may dismiss or overlook the signs. Body horror should blend with erotic undertones—fertility, swelling, lactation, cravings—while never losing the sinister aspect. The entity inside may manipulate the host from within, growing stronger as the pregnancy advances. Themes: body autonomy violation, fear of birth, transformation into something alien.