Menstrual cycle higher level of substance abuse is due to decreased self-control as a result of the higher metabolic demands during the luteal phase. Infrequent or irregular ovulation is called "oligoovulation". The absence of ovulation is called "anovulation". Normal menstrual flow can occur without ovulation preceding it: an anovulatory cycle. In some cycles, follicular development may start but not be completed; nevertheless, estrogens will be formed and stimulate the uterine lining. Anovulatory flow resulting from a very thick endometrium caused by prolonged, continued high estrogen levels is called "estrogen breakthrough bleeding". Anovulatory bleeding triggered by a sudden drop in estrogen levels is
Progesterone (medication) are up to 100-fold higher than during normal menstrual cycling, although levels increase gradually over the course of pregnancy. Oral dosages of progesterone of as high as 3,600 mg/day have been assessed in clinical trials, with the main side effect being sedation. There is a case report of progesterone misuse with an oral dosage of 6,400 mg per day. Administration of as much as 1,000 mg progesterone by intramuscular injection in humans was uneventful in terms of toxicity, but did induce extreme sedation and somnolence accompanied by nearly unarousable sleep, though the individuals were still able to be awakened with