* Foetal ovaries produce oestradiol, but this does NOT defeminize the hypothalamus.
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* Foetal ovaries produce oestradiol, but this does NOT defeminize the [[Hypothalamus_-_Anatomy_%26_Physiologyhypothalamus]].
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* A protein called alpha-fetoprotein binds oestradiol to prevent it from crossing the blood brain barrier, therefore oestradiol cannot effect the hypothalamus.
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* A protein called alpha-fetoprotein binds oestradiol to prevent it from crossing the blood brain barrier, therefore oestradiol cannot effect the [[hHypothalamus_-_Anatomy_%26_Physiologyypothalamus]].
* Alpha-fetoprotein is synthesized firstly by the embryonic yolk sac and then by the foetal liver.
* Alpha-fetoprotein is synthesized firstly by the embryonic yolk sac and then by the foetal liver.