The use of urinary hormonal assessments in human studies.

The collection and analysis of urine samples provides a practical method for monitoring female reproductive events in non-laboratory and non-clinic populations. Collection of biologic samples permits objective assessment of reproductive health endpoints in epidemiologic studies and for epidemiologic research purposes can provide validation of information provided by the subjects, especially outcomes which are usually concealed and thus unknown to the participant. Urine sampling has several advantages over the collection of blood samples, such as simplicity, non-invasiveness, and cost efficiency. Several studies have shown that endocrine information similar to that obtained in blood samples can be obtained from assays of daily urine samples. The measurement of human chorionic gonadotropin in daily and selected urine samples has been incorporated into several recent epidemiologic studies focusing on early fetal loss, and ovarian and pituitary hormone metabolites have been measured in daily urine samples to evaluate ovarian function in studies focusing on women's reproductive health. As the strategy of urinary monitoring becomes more accepted as a legitimate research tool, laboratory methods are being modified to improve performance, reduce costs and adapted to sophisticated algorithms using multiple hormonal measurements to identify a number of end-points.