To date, there has been scant research done by medical scientists on the menstrual cycle. Many of the photographs of cervixes are from a menstrual cycle study conducted by nine women at the Feminist Women's Health Center in 1975, which greatly increased our knowledge about healthy changes during the menstrual cycle. Three of the nine participants' cervixes are shown here. In addition to daily photographs, the women made 36 different observations of daily changes in the appearance of the cervix, vagina and clitoris; the amount, color and texture of secretions; and recorded outside factors which they felt might influence their cycle.

The brief health background for each woman is included, where it is relevant, to illustrate the range of experience the women have had with childbirth, abortion, birth control, sex and vaginal conditions. Although some of the information may not seem important, all of it does, in fact, have a bearing on that woman's condition. For example, for the pictures of the cervix, we attempted to include the precise day of the woman's cycle, because the appearance of the cervix changes from day to day. A woman's age is given to illustrate the point that the appearance of the cervix is not dependant on age.Through the photographer's lens, every feature of the cervix, vagina, and clitoris stands out. So do certain other features, like the outline of the speculum, which often appears as a circle of light. The particular angle of the cervix and the color variations from picture to picture may be more the result of the photographic process than of something different or unusual about the cervix itself.