Jumping on the Rosemary's Baby/Omen/It's Alive gravy train in the mid 70s was this screamer, also known under the much better title I Don't Want to Be Born, which, according to this poster, evidently features the teetering lower half of a toddler grafted awkwardly onto a bloody-scissors-clutching adult manhand. The weapon may be sharp, and the evocation of a young and terrified Joan Collins appropriately agonizing, but there's something about the lopsided gait of that baby that gets me giggling every time I look at it. The poor dear is obviously just taking his first steps . . . and can you imagine the added pressure of having to balance a heavy pair of pulp-dripping metal shears from your meaty male hand-head when you're just learning how to walk?!
There are indeed other pleasures to this poster (the Eileen Atkins?; that crazy dangling modifier in the big bold opening tagline; that ellipsis and exclamation point that purport to be finishing a sentence but really aren't). But nothing equals the crazy cuteness of that wobbly murder-baby. Somebody's ready for his nap!