Amennorhea, birth control and now thryroid disorder

[Dibbs]

Please give advice: My 19 yr old dtr got her period for 2 mths when she was 13 yrs old. We moved to a different city at the same time, very stressful on her. I had to leave her with dad and siblings for 3 mths while finishing Univ. She became anorexic for, I'd say a good 2 yrs. Refused treatment.Never got her period then since 13 yrs old. Started eating better as a teenager and then last August I insisted she go see a Dr about going on the birth control pill at 19 yrs old to bring on the period. It did cause the period to come. However, I noticed severe mood swings/Depression since Sept/08 until present time. (shortly after starting on the BC pill). (At least she's got her period but at what cost?) Now, the Dr. tested and said she is showing that she has hypothyroidism and needs to see a specialist about starting medication. (She is "very" skinny--now from obsession with exercise).
What is the relationship of her having Amennorhea for 6 yrs, starting the birth control pill, her depression and now thyroid disorder?? What website is good for explaining the imbalance that we could educate ourselves in, and possibly bring articles to the Specialist when we go?

[Dibbs]

No I don't know the lab results. Since she's 19 yrs old, she's considered an adult and parents have no right to know anything about your child due to privacy acts. The Dr. definately said the tests showed Hypothyroidism with her even though she's so skinny (due to past anorexia and now exercise obsession wt loss). As her Mom, "I" was diagnosed about 22 yrs ago with Hashimotos's Disease (actually they were initially misdiagnosing me after birth of 2nd baby with Hyperthyroidism---I told them i was trying to lose wt after a baby, but, long story,....I don't think most Dr's realize that "post partum" your hormones are so screwed up that it can cause funny things to happen to your thyroid gland.) That is why I believe that my dtr's problems now with her thyroid tests are a result of having "Amennorhea" from anorexia/extreme wt loss. &/OR recently starting the birth control pill to bring on the period.

[redheadaussie]

Hypothyroidism is usually a weight gain issue not a weight loss issue. Most people find it difficult to lose weight even when excersing when hypo. Are you sure she is hypo?
  I know from my own personal experience I lost a ton of weight and actually was anorexic but not through starving myself, I ate like a horse! I had undiagnosed hyperthyroidism.
   It seems that if she had no period for all that time, it could well be hyperthyroidism.
Having said that, it could well be she is hypo and she has been dealing with anorexia as an emotional issue entirely separate to any thyroid issues.
  The birth control pill tricks the body into thinking it is pregnant, then when you stop taking the pill and take the 'sugar' pills to allow a period,you are actually in effect coming off the hormones which trick the body into having a period! Hence why she could be having mood swings/depression. Yes being hypo can give mood swings and depression too. So you have an overlap of symptoms here.
Do you know what her lab results were? Because these are very important in knowing her true thyroid condition, you really need to ask for a copy and post them here so we can help.
  I hope that gives you some peace of mind.