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 is when a woman who has been having normal menstrual cycles stops getting her periods for 6 months or longer. Women who are pregnant, breastfeeding, or in menopause are not considered to have secondary amenorrhea.