Detection of the pre-ovulatory period using a vaginal probe in the home.

Through seven of eight consecutive cycles, a volunteer used an opto-electronic vaginal probe to record at home her daily values of vaginal back-scattering (VBS) of infrared light, at the same time as taking her daily oral temperature (BBT). Under the basal conditions used, VBS reflects vaginal changes influenced by estrogenic hormones. Each of the seven VBS curves showed a characteristic rise and fall during the first part of the cycle, preceding both inguinal pain and the BBT midcycle minimum. Periods of likely high fertility could be defined by two criteria which were applicable to all cycles recorded in this subject, and recognizable at the time of observation.