If you mean aerial drones, some number more than 670,000 UAVs have been registered by the FAA. It has been estimated that something like 1 million will be flying by the New Year 2018. I guess that some 50 industries use drones with something like 30,000+ women and men learning to be commercial, etc pilots.
1 Secondary amenorrhoea is where an established menstruation has ceasedâfor three months in a woman with a history of regular cyclic bleeding, or nine months in a woman with a history of irregular periods. 2  This usually happens to women aged 40â55.
Secondary amenorrhea: The cessation of menstruation for abnormal reasons. Causes include anorexia nervosa, disease of the female reproductive tract, and overexercise. Secondary amenorrhea can also be caused by certain medications, notably the birth control medication medroxyprogesterone (brand name: Depo-Provera); in this case, amenorrhea is an expected effect.