The Luteinized Unruptured Follicle Syndrome and Endometriosis

Abstract

The identity of luteal structures was evaluated laparoscopically in 199 women. All had evidence of ovulation as judged by dated endometrial biopsies and/or elevated levels of plasma progesterone or urinary pregnanediol. Luteal structures were identified in 159 cases. The stigma was present in 32%, absent in 38%, and questionable in 30% of the latter. No significant differences in the distribution of these findings were observed between patients with endometriosis and patients with male or tubal causes of infertility. However, in patients with clinically diagnosed ovulatory dysfunction, stigmata were observed significantly less frequently. The frequency of stigmata was not related to the varying severity of endometriosis. The earliest time in the menstrual cycle when the stigma was identified was on the day of the basal body temperature (BBT) dip prior to its rise and when the endometrium was late-proliferative. The latest was 11 days after the BBT dip and on day 26 according to endometrial histology. Uncertainty as to the presence of the stigma was frequent. The stigma was present in 33% of women with endometriosis. In some, a corpus luteum with the stigma and endometriosis were present on the same ovary. The hypothesis postulated by some investigators that the luteinized unruptured follicle (LUF) syndrome may be the cause of infertility in women with endometriosis does not appear to be accurate. However, endocrine factors probably play a role in the origin of LUF.