Abstract: A method for detecting the onset of labor in a patient, which comprises analyzing a body fluid of the patient for estriol concentration; correlating the concentration with a standard value; and relating a higher concentration of estriol relative to the standard value as an indication of potential onset of pre-term labor. The standard is usually selected from the group consisting of (1) a predetermined range of estriol concentrations for the body fluid in normal pregnant humans at a preselected time relative to normal, full-term delivery, or (2) a previously measured estriol concentration of the same body fluid of the same pregnant human. Use of this method does not require determination of an estriol/progesterone concentration ratio in the body fluid being test.

Abstract: A method of monitoring tocolytic therapy, which comprises determining a first concentration of estriol in a body fluid of a pregnant patient undergoing or diagnosed as a candidate for undergoing treatment with a tocolytic agent and, based on the value of the first concentration relative to a standard, either initiating, continuing, discontinuing, or modifying the treatment.