Are missed period due to pituitary gland problems?

recent history: irregular periods (every other week) get on birth control, subsided. got rotten b.c. and it continued. Got on the shot and used it from Sept to November. Had precancerous prob previous ( to the point to where this doc considered necessary me to have surgery and after all the sudden he arranged not too.) and im concerned now that because of the shot my likelihood were increased on getting ovarian cysts and cancer or what not. Also, i am not have a period. from my research its prob from the shot but whos to influence its not having anything to do beside pituitary problems or cancer or cysts. Im having some issues on trusting my doctor but ive gone to him for 3 almost 4 years and so have another friend of mine. i just dont see y even though he know about my precancerous postion y he would put me on depo knowing that it increases risk. or am i lately being paranoid? Have you come across PCOS surrounded by your research?
PCOS shows up in different severities and different combinations of symptoms for respectively woman affected and it is one of the top ten misdiagnosed 'diseases' contained by women according to a Reader's Digest Article. Up to 10% of women in their child attitude years have PCOS although plentiful either do not know, are misdiagnosed or are not diagnosed for years.
Read up on PCOS (see association below) and if you feel your symptoms could plummet into the PCOS category, see your doctor about getting a referral to an endocrinologist.
http://www.womens-health.co.uk/pcos.asp
See sub-menu on disappeared - there are 14 page.
Google PCOS and you'll find tons of info.
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