Childbirth may result in hair loss. It's common for many women to notice hair loss about 3 months after they've had a baby. This too, is caused by hormones. But this is not something to worry about. You see, during pregnancy, hair that normally falls out is kept in by high levels of hormones. Once the hormones have returned to pre-pregnancy levels, this extra hair falls out. The normal cycle of hair growth and loss then begins again.