Perimenopause is the period leading up to menopause. The World Health Organization defines perimenopause as the phase during which hormonal, biological, and clinical changes begin. Studies have shown that up to 90 per cent of women may experience perimenopausal changes, beginning as early as age 36. Researchers from Harvard School of Public Health and Brown University School of Medicine analyzed self-reported data on menstrual cycle patterns and financial histories for more than 600 premenopausal U.S. women between ages 36 and 45. They found that women who said they had lived through periods of financial hardship both as children and as adults were 80 per cent more likely to experience perimenopausal symptoms. Lauren Wise, a doctoral student in the Department of Epidemiology at the Harvard School of Public Health and lead author of the study, said: “Our findings suggest that lifetime socioeconomic position may influence ovarian function more strongly than either childhood or adult socioeconomic position alone.” The research appeared in the November 2002 issue of the Journal of Epidemiology and Community Health and was supported by grants from the National Institute of Mental Health.