hmm hyperthyroidism does affect menstrual cycle. in addition if any1 know how prolactine affect the menstrual cycle too? I THINK (don't quote me, this is just my theory), normally there is thyrotropin-releasing factor (TRF) released from the hypothalamus which stimulates realese of thyroid stimulating hormone (TSH) from the pituitary --> thyroid stimulation. But TRF also stimulates prolactin release.
Increased Prolactin stimulates breast milk production, but also decreases sex hormones - hence the amenorrhoea. BUT i'm pretty sure this is the case for HYPOthyroidism.. as the brain is trying to stimulate the thyroid to release more.
I don't think it would occur in hyperthyroidism unless it was actually like a secondary hyperthyroidism, with the primary problem being in the hypothalamus secreting to much TRF.
Hope this made sense.
addition:
This is a hard question, and to be honest I don't know if my answer is right. Prolactin decreases levels of oestrogen, or FSH ... something like that anyway... and that's how it would effectively cause amenorrhoea. That's why you don't get periods (or get pregnant for that matter) early post-partum while you're breast feeding.
If you had an abnormal amount of prolactin, you may also notice some galactorrhoea (milky nipple discharge) I guess. who told you that it will cause amenorrhea?
thryoid has nothing to do with menstral cycle which are caused by other types of hormones, such as estrogen, progesterone, LH, FSH, etc; it is not caused by thryoid hormone at all |
