A multitude of errors in menstrual-synchrony research: replies to Weller and Weller (2002) and Graham (2002).

This article replies to commentaries by A. Weller and L. Weller (2002) and by C. A. Graham (2002). The author of this reply argues that A. Weller and L. Weller merely defined away the problem of cycle variability for synchrony by assuming either that all cycles are 28-days long or that the expected difference between 2 cycles is 1/4 the mean of the cycles of 2 rhythms. In her commentary, C. A. Graham stated that A. Weller and L. Weller's later research did not use recall data, but the author of this reply shows that this is not true. Menstrual-synchrony research taken as a whole is plagued by a multitude of systematic errors that lead inevitably to the conclusion that there is no evidence for menstrual synchrony among women.