Menstrual cycle phase and psychiatric admissions.

Several surveys have demonstrated increased psychiatric admissions during the para-menstrual phases of the menstrual cycle (4-5 days before and during the onset of menses). We assessed menstrual cycle phase in 51 carefully diagnosed women at the time of emergency psychiatric admission and contrasted their cycle phase distribution with 113 normal hospital staff members assessed at random upon arrival at work. Consistent with other studies, 47% of psychiatric admissions occurred during the para-menstrual phase in contrast to 22% of staff controls (chi 2 = 9.27; df = 1; P = 0.002). Within the group of psychiatric patients, 33.3% of admissions occurred within 4 days of the onset of menses (chi 2 = 12.45; df = 6; P = 0.052). There were no significant phase differences found between major depressive and schizophrenic patients, between acutely suicidal and non-suicidal patients, and no significant correlation was noted with depression rating scales. Thus, it appears that menstrual cycle entrainment and associated late luteal phase biological changes may have additive effects which are sufficient to exacerbate the expression of psychiatric disorder in vulnerable patients, independent of their diagnosis.