Thinning hair is determined by genetic and hormonal factors. If you are genetically predisposed to thinning hair, it may begin as early as your late teens. Among women a general thinning of hair by the age of 35 is called androgenic alopecia. Almost 40 percent of women will experience it by the age of 35. If you are experiencing hair loss or thinning without any history of thin hair in your family, you must visit a physician. It could arise due to hormonal changes in your body, poor diet or an undetected previous illness. These factors can disrupt the growth of hair follicles and once the underlying reason is taken care of, your hair will retain their normal growth.

Another major factor for most women in hair thinning and loss is post partum hair changes. The life cycle of a hair has three stages; 85 to 90 percent of your hair is usually in the growth phase. The remaining are in resting or shedding phase. During pregnancy, the high levels of estrogen in your body prolong the growth phase. When estrogen reaches its pre-pregnancy levels, the hair that should have gone into a resting period are shed. This increases your hair fall. Again during breastfeeding estrogen levels drop increasing thin hair and hair loss.