The question of paracyclic ovulation

3 cases of histological changes indicative of supplementary ovulation which were diagnosed during gynecological surgery (for supravaginal amputation of the uterus uterine myoma and tubular pregnancy) are discussed. In the first 2 cases corpora lutea were foun d in 1 or the other ovary in various stages of development. The 3rd case was particularly interesting in that corpora lutea were found in both ovaries suggesting the possibility of simultaneous ovulation or ovulation occurring at different times during a single cycle. Menstrual conception and parturition data in a 4th case demonstrate th e possibility that pregnancy might occur from a supplementary ovulation. It is suggested that even in cases of regular menstrual cycles psychological or other factors might induce paracyclic ovulation.