I'm 50 years old and my right breast has gradually decreased in size over the past year. I have regular mammograms every year, as well as an annual physical. I forgot to mention to my doctor the noticeable size difference. Are there any reasons, other than hormones and aging, that would make my breast shrink. I have no symptoms (tingling, sensitivity). My weight has remained consistent my entire adult life. I'm a healthy, active person still having a regular menstrual cycle every 25 days.