Sex identification of bloodstains by radioimmunoassay of sex hormones

A forensic application is reported for the sex determination of subjects whose dried bloodstains are analyzed by radioimmunoassay for testosterone and progesterone. Blood specimens of ten males and 15 females were collected, prepared as bloodstains, and then assayed at four-different time intervals for testosterone (T) and progesterone (P) contents up to 3 months later. The ratio of the two hormone contents ($\text{P}\text{T}$) was used to establish the sex origin of the dried blood specimens.