These are purportedly the after-hours bathtub ruminations of a clinical sex therapist (Psychiatry, New York Hospital-Cornell University Medical Center), but they read more like prepared medical lectures. Dr. Offit has covered some of this territory with wit and humanity before (The Sexual Self, 1977), so it comes as a distinct disappointment to find so little of real substance here that the lay person can latch onto. Much is made, for example, of hormones--the extent to which they govern the emotional ups and downs of the menstrual cycle, or the way in which they curb sex drive in pregnancy (not only in expectant mothers, but, responsively, in the men as well). Only occasionally, however, does the doctor share the insights and frustrations of day-to-day counseling: she's wry on the subject of extramarital affairs (originally she prohibited her patients from having them, but relented when she realized her practice would ""wither and die""). She speculates on the origins of certain sexual behaviors: fellatio may be ""partly a pleasurable extension of animal grooming""; nymphomania may derive from the manic phase of manic-depressive psychosis. But it's difficult to tell who all this is intended for: it's simply too dry and unfocused for most couples in need of help, and it doesn't make for very good incidental reading.