My periods have always been pretty normal. I have to have a thyroidectomy due to a very large multinodular goiter. My doctor is also concerned I might have a malignancy. Should I expect a change in my menstrual cycle? Are the replacement hormones good enough to keep things normal? I guess its the least of my worries but something I am wondering about. I've never needed thyroid meds before. I'm not worried about fertility, I am done having kids. After your thyroid is removed you will need thyroxine replacement. Your periods will behave like those of someone with an under-active thyroid if you do not get adequate replacement. This will usually be infrequent or very heavy periods. So as long as you have adequate replacement you will be OK. It shouldn't have any effect on your periods. The hormones that regulate periods don't come from the thyroid. Thyroid is more like the accelerator in your car. It controls the rate at which your body's processes run. There might be a slight off time just because you're having major surgery, but with time it will return to normal. | 