Figure 3.

No effects of ovulation on testosterone concentrations. Normalized testosterone concentrations in the saliva from the males in the 29 included couples (one couple was excluded because of difficulties in determining the ovulation date). Bars for standard deviation on the Y-axis are depicted against cycle day on the X-axis. No difference could be seen between day 4 and 14 in the multiple regression analysis (p < 0.971), and an estimation of similarity by type II error(β)-analysis using pairwise power calculation showed that the difference between these two points was less than 14.3% (β = 0.05).