A Kiss Before Dying: Ira Levin

Dorothy meets a handsome young man with an eye for her inheritance while she is in her sophomore year. They are to be married and her life will be blissful; but Dorothy is pregnant and her fiance's plans are ruined, for Dorothy would be disinherited if her father discovered the truth.

So the young man provides his bride to be with some pills that will solve the problem. Soon there will be no baby - and perhaps no Dorothy either... A Kiss before Dying, Levin's first novel, earned him the 1954 Edgar Award for Best First Novel and is regarded as a modern classic.