Women tend to lose hair when they are especially sensitive to DHT in the scalp. This most often happens during and following the menopause, due to the decrease in female hormones and relative increase of male hormones such as DHT. This hair loss does not occur in the same pattern as it does for men, and is rarely as severe. Changes in hormones that lead to hair loss could be caused by thyroid disorders and should be checked by a medical professional. This can also cause weight gain.
Pregnant women, who have increased levels of progesterone, may experience some hair loss. The progesterone causes hair follicles to briefly stop. Again, this is only temporary.
Women with a deficiency of iron called anaemia can suffer from hair loss. This can be reversed with a diet with sufficient iron.