PubMed1975
Two young women developed unconjugated hyperbilirubinemia that fluctuated with the menstrual cycle. They were otherwise healthy, and there was no evidence of hematologic or chronic liver disease. Serum unconjugated bilirubin rose concomitant with the rise of basal temperature during the premenstrual period, and it declined immediately after the end of menses. Administration of progesterone during the postmenstrual period elevated unconjugated bilirubin. A close relation of hyperbilirubinemia to female hormones was suggested. The condition may be called "constitutional unconjugated hyperbilirubinemia with a menstrual cycle.