Whitten, W

Nature, vol. 401, no. 6750, p. 232, 16 Sep 1999

There is controversy surrounding the issue of whether there is menstrual synchrony in women who live together, particularly in the case of the coupled-oscillator model developed to explain similar data from rats. Stern and McClintock have proposed that the rat model applies to women, with the effect being mediated by two opposing axillary "pheromones" that could affect major reproductive events and have potential for "either contraception or treatment of infertility". This claim is based on data derived from four cycles from each of 20 subjects treated with axillary compounds to change the cycle length from that of each subject's baseline cycle. Subjects' upper lips were wiped daily with pads worn in the axillae of donors in follicular or ovulatory phases of their cycles. The cycles of subjects wiped with follicular pads appeared to be shortened by 1-14 days, whereas cycles of those wiped with ovulatory pads were longer by 1-12 days. One-third of cycles did not change or changed in the opposite direction.