April 11, 2011 -- Contrary to what some people think, women’s voices don’t change at different points of time over their menstrual cycle.
A new study shows that women’s voices remain steady throughout the hormonal changes associated with their menstrual cycle and don’t become any higher or more shrill at certain times during the cycle.
Researchers say the results contradict previous studies that suggested the tone of women’s voices rises as ovulation approaches.
"Previous studies were subjective [in their assessments] or measured only three or four parameters," researcher Neal S. Latman, PhD, associate professor of biology at West Texas A&M University, says in a news release. "Or they analyzed single vowel tones, but people don't speak in single vowels. They speak in sentences."
For the study, presented at the Experimental Biology 2011 meeting in Washington, D.C., researchers analyzed 175 voice samples provided by 35 female study participants.
The women kept diaries to track their menstrual cycles in the month leading up to the study. Then the women recorded voice samples at four points over their next two menstrual cycles.
For each voice sample, the women recorded the same question: “Yesterday, did the kindergarten children watch television after breakfast?” Researchers say the question was selected because it is voice rich and provides a variety of voice characteristics.
At the end of the study, the voice samples were analyzed by voice analysis software to measure eight different voice parameters, such as degree of voice breaks, fundamental frequency, and shimmer (which measures varying degrees of loudness).
The results showed no differences in these eight voice parameters between the different menstrual cycle changes for each woman.
In addition, there were no differences in voice characteristics for each woman from menstrual cycle to cycle or between women who were using hormonal contraceptives and those who were not.
This study was presented at a medical conference. The findings should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.