Spring 2011 Research Update
Selected New Publications
Cerny, J., & Janssen, E. (2011). Patterns of sexual arousal in homosexual, bisexual, and heterosexual men. Archives of Sexual Behavior, doi:10.1007/s10508-011-9746-0.
George, W.H., Davis, K.C., Heiman, J.R., Norris, J., Stoner, S.A., Schacht, R.L., Hendershot, C.S., and Kajumulo, K.F. (2011). Women's sexual arousal: Effects of high alcohol dosages and self-control instructions. Hormones and Behavior, doi:10.1016/j.yhbeh.2011.03.006.
Janssen, E. (2011). Sexual arousal in men: A review and conceptual analysis. Hormones and Behavior, doi:10.1016/j.yhbeh.2011.03.004.
Macapagal, K.R., Rupp, H.A., & Heiman, J.R. (2011). Influences of observer sex, facial masculinity, and gender role identification on first impressions of men's faces. Journal of Social, Evolutionary, and Cultural Psychology, 5(1), 92-105.
Womens’ reproductive cycle through the lifespan — a bio-anthropological perspective
Photo Credit: Jennifer Burch
From infertility to hormone replacement therapy, major medical and research centers are focusing on women’s reproductive issues and trying out new solutions. Research on causes and treatments are almost exclusively based on data from women in industrialized countries.
But there are other stories coming out of the Bolivian highlands, where women and men are under environmental stress due to seasonal variation in workload and food intake. For nearly 20 years, as Director of Project REPA (Reproduction and Ecology in Provincia Aroma), Virginia Vitzthum has been following the reproductive health of women in the Bolivian highlands pregnancy, pregnancy loss, childbirth, and now, menopause (see Kinsey Today). This research illuminates the roles of environmental, behavioral, dietary, and genetic factors in women’s reproductive health.
In April, Dr. Vitzthum and her colleagues, including IU student research assistant Jennifer Burch, presented some recent findings from the REPA project at the Annual Meeting of the Human Biology Association in Minneapolis MN.
The timing of menopause in a population with high mortality risks.
Age at menopause is predicted to be relatively earlier in populations characterized by high adult mortality risk, especially if maternal survival is a major determinant of newborn survival. Such conditions are common in many non-industrialized populations including in the Bolivian altiplano, the locale for Project REPA, a longitudinal study of reproductive functioning and health in rural Bolivians.
In preliminary analyses, the median age of menopause among these women was 48 years, at the lower end of the range of reported ages at menopause in other populations (e.g., Nepal = 46.8 yrs, US whites = 51.4 yrs). Those Bolivian women with a younger age at menarche (first menstrual cycle) were found to have a younger age at menopause (menarche at 12 years of age was associated with age at menopause of 46 years; menarche at 16 years of age was associated with an age of menopause of 50 years). Higher socioeconomic status was also associated with an earlier age at menopause The research team is currently examining the potential influence of other factors, including nutritional status and lifetime fertility, on the timing of menopause in these rural Bolivians.
Presented by Jennifer Burch, Jonathan Thornburg (IU, Astronomy), and Virginia Vitzthum, and funded bythe Office of the Vice Provost for Research, Indiana University, Bloomington.
Investigating trade-offs between lactation and maternal somatic investment in breastfeeding rural Bolivian women. (with Amanda Rollins,Indiana University Dept of , Hilde Spielvogel,Bolivian Institute of High Altitude biology, and Jonathan Thornburg,IU Astronomy)
Breastfeeding provides the best nutritional resource for a young infant and also confers invaluable immunological benefits, but breastfeeding is metabolically ‘expensive.’ This energy demand can be met by drawing on maternal fat stores and/or changing maternal food intake and activities during lactation, options that may not be feasible if food is scarce and/or maternal labor is essential. This ongoing study is evaluating height, weight and other post-partum changes of breastfeeding women in the Bolivian REPA study.
Funded by National Science Foundation (SBR 9506107), University of California Regents, and Indiana University, Bloomington.
The researchers also issued a technical report, showing that the relationship of salivary to serum progesterone in Bolivian women is comparable to that in other populations.
Because refrigeration and medical equipment are not always optimal, and samples have to be transported to laboratories in the US and Europe for testing, sampling hormones in the field can be tricky business. Furthermore, collecting blood samples for measuring hormones may be invasive.
Salivary progesterone (P) concentration is widely used in field studies as a relatively easy-to-measure proxy for serum Progesterone. In this study, the team analyzed new data collected specifically to investigate the relationship of salivary P to serum P in Bolivian women and concluded that salivary P is a reliable proxy for serum P in Bolivian women and (assuming comparable assays) that comparisons of salivary P are valid across populations.
Presented by Jonathan Thornberg, Jennifer Burch, Virginia Vitzthum, and Rose Stewart (CISAB Lab) of Indiana University, and Diva Bellido, Hilde Spielvogel, and Lourdes Echalar from the Bolivian Institute of High Altitude Biology.
Funded by Instituto Boliviano de Biología de Altura, La Paz, Bolivia; Indiana University, Bloomington; Kinsey Institute for Research in Sex, Gender, and Reproduction; and the Center for the Integrative Study of Animal Behavior at Indiana University.
Photo Credit: Jennifer Burch
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