Hello and welcome to ‘Ask A Doctor’ service.
I have reviewed your query and here is my advice.
Hormone imbalance can explain
irregular periods but usualy this conditioon do not cause low blood pressure.
You mention that you had low blood pressure when you stand up.This is called
orthostatic hypotension.
Orthostatic hypotension is a form of low blood pressure that happens when you stand up from sitting or lying down.
Orthostatic hypotension can make you feel dizzy or lightheaded, and maybe even faint.
There is not a specific treatement to fix orthostatic hypotension.
Anyway,if this problem persist i suggest to discuss with your local doctor.
A low-dose birth control pill that containing a combination of
estrogen and
progesterone may help.If the low blood pressure persist,your doctor may prescribe a medication to treat the orthostatic hypotension, such as fludrocortisone(for example)
Hope i have answered to your question.
Let me know if i can assist you further.
Regards