what is the hormone in pregnant women that causes the hair to grow?

Hi sweetmita-ga,

The hormone is estrogen. According to the American Pregnancy Association:

  "During pregnancy there is an increase in the level of
   estrogen hormones. The estrogen hormone causes hair to
   remain in the growing phase and stimulate the growth
   of your hair."

   http://www.americanpregnancy.org/pregnancyhealth/hairloss.html

Regards,
eiffel-ga


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