Mammographic density changes during the menstrual cycle

The ability to detect small tumors is impaired in dense mammograms, It has been suggested that the sensitivity of mammograms could be lower in mammogr ams obtained during the luteal phase of the menstrual cycle. We examined th e change in mammographic density from the follicular to the luteal phase of the menstrual cycle in 11 women. Although the average increase in densitie s was quite small (1.2%; P = 0.08), six women had clinically significant in creases (1.4-7.8%), suggesting that premenopausal women should undergo mamm ographic examinations in the follicular part of the menstrual cycle.