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 can be caused by: 1  Pregnancy (the most common cause) 2  Breast feeding. 3  Menopause, the normal age-related end of menstruation.  Emotional or physical 1  stress. Rapid weight loss.  Frequent strenuous 1  exercise. Hormonal birth control methods, including birth control pills, the patch and long acting progesterone.  Polycystic ovary syndrome.