Why does the time in the menstrual cycle matter for a breast MRI (post mastectomy)?

I need to have an MRI done. I had a bilateral mastectomy 5 years ago. Why are they asking me to come in between day 7 and 14 of my menstrual cycle if I technically don't have breast tissue?

Doctor Answers 2


Prior to mastectomy, the menstrual cycle is important in planning the timing of the exam. The MRI is most accurate when the hormones are at their lowest - generally 7-10 days after the first day of menstruation. The breast are less dense then and it is easier to see abnormalities. After menopause or mastectomy, there is no need for this timing. Even when nipples are preserved, the residual breast tissue should be minimal and MRI will be accurate regardless of the hormone cycle.  Apparently the scheduler or radiologists don't realize this or don't realize you have had a mastectomy. Schedule it whenever you like. Good luck and take care.


I appreciate your question.
I have never heard of timing for menstrual cycle but Im guessing they want to see the breast at a higher point of hormones to check.

The best way to assess and give true advice would be an in-person exam.
Please see a board-certified plastic surgeon that specializes in aesthetic and restorative breast surgery.

best of luck!

Dr Schwartz

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