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TREMIN Research Program on Women's Health (tremin)


The Population Research Institute (PRI) is currently evaluating the SODAPOP service. The ability to extract a data set containing a subset of variables will not be supported after September 15, 2016.

The data collections in SODAPOP will still be available from the PRI. If you should have concerns about this change to the SODAPOP service or need to access some of the data, contact the PRI's Computational and Spatial Analysis (CSA) core at

STIPULATIONS FOR USE: PassWord Protected Access to SodaPop. Researchers can review the variables in the dataset as well as the annual surveys at Data Code Book . The data are password protected and will be accessible only after full approval is given by the director/staff person.


DESCRIPTION: The TREMIN Research Program on Women's Health is one of the world's oldest ongoing research programs dedicated to studying menstration and women's health. Initiated in 1934 by Dr. Alan E. Treloar at the University of Minnesota, this unique intergenerational study was established to document menstrual cycle variations. It has followed several thousand women throughout their reproductive lives. TREMIN participants provide a wide variety of information related to menstruation and health by completing a annual health survey and daily menstrual diary. Initially, 2,350 University of Minnesota women volunteered to participate in the study in the 1930s. A second group of 1,600 women was enrolled between 1961-1963. In 1965, a panel of 1,000 native Alaskan women was invited to participate in the program. Women in the study range from their teens to mid-nineties and represent fifty states and twenty-five foreign countries. Data collection ended in 2009, 75 years worth of data. 

OBTAINING PERMISSION TO ACCESS THE DATA: Individuals interested in accessing TREMIN data should submit a brief research proposal, proof of Human Subjects IRB approval, and completed  Data Use Agreement and Data Request Forms to the SodaPop team ( for review.  Final approval will be granted by the TREMIN Director after review of all application materials. 

Download TREMIN Files

PRINCIPAL INVESTIGATOR(S):  The study was initiated in 1934 as the Menstrual and Reproductive History (MRH) Study by Dr. Alan E. Treloar at the University of Minnesota. After Dr. Treloar's retirement,the TREMIN program moved to the University of Utah under the direction of Dr. Ann Voda and was called the Tremin Trust Program. Upon Dr. Voda's retirement, the TREMIN program moved to The Pennsylvania State University under the direction of Dr. Phyllis Kernoff Mansfield where it currently resides.

ORIGINAL DATA FILES:  Access to unprocessed files limited to Penn State PRI researchers.


The first publication based on TREMIN data was in 1967:

Treloar, A E (1967)" Variation of the human menstrual cycle through reproductive life".  International journal of fertility (0020-725X)12 (1), p. 77.

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