There is a perceptual difference between male and female speech in fundamental frequency and, less significantly, in formant frequencies. These characteristics are physiologically determined to a great extent, and thus speakers exert little control over these characteristics in their normal utterances. The present study investigates whether some characteristics of fundamental frequency are also manipulated by speakers to make speech quality more feminine. The results of our experiment show that the delay of the F0 fall that signals a lexical accent is associated with femininity in Japanese.